A 11 ID 3 3A^SMZ

N1ST PUBLICATIONS NIST SPECIAL PUBLICATION 260-1 1 2

U.S. DEPARTMENT OF COMMERCE/National Institute of Standards and Technology

Standard Reference Materials:

Glasses for Microanalysis:

SRM's 1871-1875

icLOO

J57 >60- 112 R. B. Marinenko, D. H. Blackburn, and J. B. Bodkin

1990
NATIONAL INSTITUTE OF STANDARDS

TECHNOLOGY

Research Information Center

Gakhersburg, MD 20899

DATE DUE

Demco. Inc. 38-293
Standard Reference Materials:

Glasses for Microanalysis:

SRM's 1871-1875

R. B. Marinenko

Gas and Particulate Science Division National Measurement Laboratory

National Institute of Standards and Technology

Gaithersburg, MD 20899

D. H. Blackburn

(retired)

U.S. DEPARTMENT OF COMMERCE, Robert A. Mosbacher, Secretary NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, John W. Lyons, Director

Issued February 1990

and

J. B. Bodkin

Mineral Constitution Laboratories The Pennsylvania State University

University Park, PA 16802
National Institute of Standards and Technology Special Publication 260-112

Natl. Inst. Stand. Technol. Spec. Publ. 260-112, 60 pages (Feb. 1990)

CODEN: NSPUE2

U.S. GOVERNMENT PRINTING OFFICE WASHINGTON: 1990

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402-9325
Preface

Standard Reference Materials (SRM's) as defined by the National Institute

of Standards and Technology (NIST) are well-characterized materials,

produced in quantity and certified for one or more physical or chemical

properties. They are used to assure the accuracy and compatibility of measurements throughout the Nation. SRM's are widely used as primary

standards in many diverse fields in science, industry, and technology, both within the United States and throughout the world. They are also used extensively in the fields of environmental and clinical analysis.

In many applications, traceability of quality control and measurement

processes to the national measurement system is carried out through the mechanism and use of SRM's. For many of the Nation's scientists and

technologists, it is therefore of more than passing interest to know the details of the measurements made at NIST in arriving at the certified

values of the SRM's produced. The NIST Special Publication 260 Series is a series of papers reserved for this purpose.

The 260 Series is dedicated to the dissemination of information on different phases of the preparation, measurement, certification, and use

of NIST SRM's. In general, much more detail will be found in these papers than is generally allowed, or desirable, in scientific journal

articles. This enables the user to assess the validity and accuracy of

the measurement processes employed, to judge the statistical analysis, and to learn details of techniques and methods utilized for work

entailing greatest care and accuracy. These papers also should provide

sufficient additional information so SRM's can be utilized in new

applications in diverse fields not foreseen at the time the SRM was originally issued. Inquiries concerning the technical content of this paper should be directed to the author(s) . Other questions concerned with the availability, delivery, price, and so forth, will receive prompt

attention from:Office of Standard Reference Materials

Bldg. 202, Rm. 204 National Institute of Standards and Technology

Gaithersburg, MD 20899

William P. Reed, Chief

Office of Standard Reference Materials

iii
CONTENTS

Preface iii Introduction 1 Preparation 1 Homogeneity 2

Quantitative Analysis 4 SRM 1871, Lead-silicate glasses 5 SRM 1872, Lead-germanate glasses 6 SRM 1873, Barium-zinc-silicate glasses 6 SRM 1874, Lithium-aluminum-borate glasses 6 SRM 1875, Aluminum-magnesium-phosphate glasses 6 Wet Chemistry 6 Emission Spectrometry 6 Neutron Depth Profiling 7 Conclusions 8 Acknowledgments 8 Tables

1 . SRM 1 87 1 , Lead-Silicate Glasses 9

2. SRM 1872, Lead-Germanate Glasses 10

3. SRM 1873, Barium-Zinc-Silicate Glasses 11 4 . SRM 1 874, Lithium-Aluminum-Borate Glasses 12

5 . SRM 1 875, Aluminum-Magnesium Phosphate Glasses 13

6. Homogeneity Evaluation of Glasses K-456, K-493, And K-523 14

7. Homogeneity Evaluation of Glasses K-453, K-491, And K-968 15

8 . Homogeneity Evaluation of Glasses K-458, K-489, And K-963 16 9 . Homogeneity Evaluation of Glasses K-495, K-490, And K-546 17

10. Homogeneity Evaluation of Glasses K-496, K-497, And K-1013 18

1 1 . Quantitative Analysis of the Lead-Silicate Glasses, SRM 1781 19

12. Quantitative Analysis of the Lead-Germanate Glasses, SRM 1782 20

13. Quantitative Analysis of Barium-Zinc-Silicate Glasses, SRM 1873 21

14. Quantitative Analysis of the Lithium-Aluminum-Borate Glasses, SRM 1874 22

15. Quantitative Analysis of the Aluminum-Magnesium 23

1 6. Voltages and Standards Used in Wavelength Dispersive Analysis . /. 24

17. Quantitative Analysis of Standard Glass K-227 25

1 8 . Wet Chemistry Procedures Used in the Quantitative Analyses 26

Figures

1 . Periodic integrator homogeneity traces of lead and silicon simultaneoulsy recorded from Glass K-493 (15 Kv, 7.5 x 10 8 A beam current). In the

traces on the right, the specimen was advanced 1-um under a 1-um

diameter electron beam after each 10-second counting period. To the left is a time-resolved trace taken from repeated 10-second counting periods on a

stationary specimen with a 20 x 20 um scanning raster. The double-headed

arrows to the right represent a range of +3VN around the average number

of counts per 10 seconds, N, for the entire trace 27

iv
2 . Periodic integrator homogeneity traces of germanium and lead simultaneoulsy recorded from Glass K-491 (15 Kv, 7.5 x 10 8 A beam

current). In the traces on the right, the specimen was advanced 1-um under

a 1-um diameter electron beam after each 10-second counting period. To

the left is a time-resolved trace taken from repeated 10-second counting

periods on a stationary specimen with a 20 x 20 um scanning raster. The

double-headed arrows to the right represent a range of ±3VH around the average number of counts per 10 seconds, N, for the entire trace 28

3 . Periodic integrator homogeneity traces of silicon, barium and zinc simultaneoulsy recorded from Glass K-489 (15 Kv, 7.5 x 10"8 A beam

current). In the traces on the right, the specimen was advanced 1-um under

a 1-um diameter electron beam after each 10-second counting period. To

the left is a time-resolved trace taken from repeated 10-second counting

periods on a stationary specimen with a 20 x 20 um scanning raster. The

double-headed arrows to the right represent a range of ±3VN around the average number of counts per 10 seconds, N, for the entire trace 29

4 . Periodic integrator homogeneity traces of magnesium, phosphorous and aluminum simultaneoulsy recorded from Glass K-497 (15 Kv, 7.5 x 10 8 A beam current). In the traces on the right, the specimen was advanced 1- um under a 1-um diameter electron beam after each 10-second counting

period. To the left is a time-resolved trace taken from repeated 10-second

counting periods on a stationary specimen with a 20 x 20 um scanning

raster. The double-headed arrows to the right represent a range of ±3VN

around the average number of counts per 10 seconds, N, for the entire trace 30

5 . SRM 187 1. Distribution plots of the results of wet chemistry, electron microprobe, and inductively coupled plasma spectrometry analyses

compared to the nominal compositions 31

6. SRM 1872. Distribution plots of the results of wet chemistry, and electron microprobe analyses compared to the nominal compositions 32

7 . SRM 1873. Distribution plots of the results of wet chemistry, electron microprobe, inductively coupled and direct current plasma spectrometry

analyses compared to the nominal compositions 33

8 . SRM 1874. Distribution plots of the results of wet chemistry, electron microprobe analyses compared to the nominal compositions 34

9. SRM 1875. Distribution plots of the results of wet chemistry, electron microprobe, and neutron activation analyses compared to the nominal

compositions 35

References 36 Addendum 37 Appendices

Certificate for SRM 1 87 1 38

Certificate for SRM 1872 40

Certificate for SRM 1873 42

Certificate for SRM 1874 44

Certificate for SRM 1 875 46

Publicity release for SRM's 1871-1875 48

v
OTHER NIST PUBLICATIONS IN THIS SERIES

Seward, R. W., ed., NBS Standard Reference Materials Catalog 1988-89, NBS Spec. Publ. 260 (January 1988)

Michaelis, R. E. , and Wyman, L. L. , Standard Reference

Materials: Preparation of White Cast Iron Spectro- chemical Standards, NBS Misc. Publ. 260-1 (June 1964) . COM74-1 1061**

Michaelis, R. E., Wyman, L. L., and Flitsch, R., Standard Reference Materials: Preparation of NBS Copper- Base Spectrochemical Standards, NBS Misc. Publ. 260-2 (October 1964). COM74-1 1063**

Michaelis, R. E., Yakowitz, H., and Moore, G. A., Standard Reference Materials: Metallographic Characterization of an NBS Spectrometric Low-Alloy Steel Standard, NBS Misc. Publ. 260-3 (October 1964). COM74-11060**

Alvarez, R., and Flitsch, R., Standard Reference Materials: Accuracy of Solution X-Ray Spectrometric

Analysis of Copper-Base Alloys, NBS Misc. Publ. 260-5 (March 1965). PB168068**

Shultz, J. I., Standard Reference Materials: Methods for

the Chemical Analysis of White Cast Iron Standards, NBS Misc. Publ. 260-6 (July 1965). COM74-

11068**

Bell, R. K., Standard Reference Materials: Methods for the Chemical Analysis of NBS Copper-Base Spectro- chemical Standards, NBS Misc. Publ. 260-7 (October

1965). COM74-11067**

Richmond, M. S., Standard Reference Materials: Analysis of Uranium Concentrates at the National Bureau

of Standards, NBS Misc. Publ. 260-8 (December

1965). COM74-1 1066**

Anspach, S . C. , Cavallo, L. M. , Garfinkel, S. B. , Hutchinson, J. M. R., and Smith, C. N., Standard Reference

Materials: Half Lives of Materials Used in the Pre- paration of Standard Reference Materials of Nineteen

Radioactive Nuclides Issued by the National Bureau

of Standards, NBS Misc. Publ. 260-9 (November

1965). COM74- 11065**

Yakowitz, H, Vieth, D. L., Heinrich, K. F. J., and Michaelis, R. E., Standard Reference Materials: Homogeneity Characterization of NBS Spectrometric

Standards II: Cartridge Brass and Low-Alloy Steel, NBS Misc. Publ. 260-10 (December 1965). COM74-

11064**

Napolitano, A., and Hawkins, E. G., Standard Reference

Materials: Viscosity of Standard Lead-Silica Glass, NBS Misc. Publ. 260-11 (November 1966).

Yakowitz, H, Vieth, D. L., and Michaelis, R. E., Standard Reference Materials: Homogeneity Characterization of NBS Spectrometric Standards III: White Cast

Iron and Stainless Steel Powder Compact, NBS Misc.

Publ. 260-12 (September 1966). Menis, O, and Sterling, J. T., Standard Reference Materials: Determination of Oxygen in Ferrous Materi- als—SRM 1090, 1091, and 1092, NBS Misc. Publ. 260-14 (September 1966). Yakowitz, H., Michaelis, R. E., and Vieth, D. L., Standard Reference Materials: Homogeneity Characterization of NBS Spectrometric Standards IV: Preparation and Microprobe Characterization of W-20% Mo

Alloy Fabricated by Powder Metallurgical Methods, NBS Spec. Publ. 260-16 (January 1969). COM74-

11062**

Paule, R. C, and Mandel, J., Standard Reference Materials: Analysis of Interlaboratory Measurements on

the Vapor Pressure of Gold (Certification of Standard Reference Material 745). NBS Spec. Publ. 260-19

(January 1970). PB190071**

Paule, R. C, and Mandel, J., Standard Reference Materials: Analysis of Interlaboratory Measurements on

the Vapor Pressures of Cadmium and Silver, NBS

Spec. Publ. 260-21 (January 1971). COM74-1 1359**

Yakowitz, H., Fiori, C. E., and Michaelis, R. E., Standard Reference Materials: Homogeneity Characterization of Fe-3 Si Alloy, NBS Spec. Publ. 260-22

(February 1971). COM74-11357**

Napolitano, A., and Hawkins, E. G., Standard Reference

Materials: Viscosity of a Standard Borosilicate Glass, NBS Spec. Publ. 260-23 (December 1970). COM71-

00157**

Sappenfield, K. M., Marinenko, G., and Hague, J. L., Standard Reference Materials: Comparison of Redox

Standards, NBS Spec. Publ. 260-24 (January 1972). COM72-50058**

Hicho, G. E., Yakowitz, H, Rasberry, S. D., and Michaelis, R. E., Standard Reference Materials: A

Standard Reference Material Containing Nominally Four Percent Austenite, NBS Spec. Publ. 260-25

(February 1971). COM74-11356**

Martin, J. F., Standard Reference Materials: National Bureau of Standards-US Steel Corporation Joint Pro- gram for Determining Oxygen and Nitrogen in Steel, NBS Spec. Publ. 260-26 (February 1971). PB

81176620**
Gamer, E. L., Machlan, L. A., and Shields, W. R., Standard Reference Materials: Uranium Isotopic Standard Reference Materials, NBS Spec. Publ. 260-27 (April 1971). COM74-11358**

Heinrich, K. F. J., Myklebust, R. L., Rasberry, S. D., and

Michaelis, R. E., Standard Reference Materials: Pre- paration and Evaluation of SRM's 48 1 and 482 GoldSilver and Gold-Copper Alloys for Microanalysis, NBS Spec. Publ. 260-28 (August 1971). COM71-

50365**

Geller, S. B., Standard Reference Materials: Calibration of NBS Secondary Standard Magnetic Tape (Computer Amplitude Reference) Using the Reference Tape Amplitude Measurement "Process A-Model

2," NBS Spec. Publ. 260-29 (June 1971). COM71-

50282**

Gorozhanina, R. S., Freedman, A. Y., and Shaievitch, A.

B. (translated by M. C. Selby), Standard Reference

Materials: Standard Samples Issued in the USSR (A

Translation from the Russian), NBS Spec. Publ. 260- 30 (June 1971). COM71-50283**

Hust, J. G., and Sparks, L. L., Standard Reference Materials: Thermal Conductivity of Electrolytic Iron SRM

734 from 4 to 300 K, NBS Spec. Publ. 260-31 (November 1971). COM71-50563**

Mavrodineanu, R., and Lazar, J. W., Standard Reference

Materials: Standard Quartz Cuvettes for High Accuracy Spectrophotometry, NBS Spec. Publ. 260-32 (December 1973). COM74-50018**

Wagner, H. L., Standard Reference Materials: Comparison of Original and Supplemental SRM 705, Narrow

Molecular Weight Distribution Polystyrene, NBS

Spec. Publ. 260-33 (May 1972). COM72-50526**

Sparks, L. L., and Hust, J. G., Standard Reference Materials: Thermal Conductivity of Austenitic Stainless

Steel, SRM 735 from 5 to 280 K, NBS Spec. Publ. 260-35 (April 1972.) COM72-50368**

Cali, J. P., Mandel, J., Moore, L. J., and Young, D. S., Standard Reference Materials: A Referee Method for the Determination of Calcium in Serum NBS SRM

915, NBS Spec. Publ. 260-36 (May 1972). COM72-

50527**

Shultz, J. I., Bell, R. K., Rains, T. C, and Menis, O., Standard Reference Materials: Methods of Analysis of NBS Clay Standards, NBS Spec. Publ. 260-37

(June 1972). COM72-50692**

Clark, A. F., Denson, V. A., Hust, J. G., and Powell, R.

L., Standard Reference Materials: The Eddy Current Decay Method for Resistivity Characterization of High-Purity Metals, NBS Spec. Publ. 260-39 (May

1972) . COM72-50529**

McAdie, H. G., Garn, P. D., and Menis, O., Standard Ref- erence Materials: Selection of Thermal Analysis Temperature Standards Through a Cooperative Study (SRM 758, 759, 760), NBS Spec. Publ. 260-40

(August 1972) COM72-50776**

Wagner, H. L., and Verdier, P. H, eds., Standard Refer- ence Materials: The Characterization of Linear Poly- ethylene, SRM 1475, NBS Spec. Publ. 260-42

(September 1972). COM72-50944**

Yakowitz, H, Ruff, A. W., and Michaelis, R. E., Standard Reference Materials: Preparation and Homogeneity Characterization of an Austenitic

Iron-Chromium -Nickel Alloy, NBS Spec. Publ. 260- 43 (November 1972). COM73-50760**

Schooley, J. F., Soulen, R. J., Jr., and Evans, G. A., Jr., Standard Reference Materials: Preparation and Use of Superconductive Fixed Point Devices, SRM 767, NBS Spec. Publ. 260-44 (December 1972). COM73-

50037**

Greifer, B., Maienthal, E. J., Rains, T. C, and Rasberry,

S. D., Standard Reference Materials: Powdered Lead- Based Paint, SRM 1579, NBS Spec. Publ. 260-45 (March 1973). COM73-50226**

Hust, J. G., and Giarratano, P. J., Standard Reference

Materials: Thermal Conductivity and Electrical Resistivity Standard Reference Materials: Austenitic

Stainless Steel, SRM's 735 and 798, from 4 to 1200

K, NBS Spec. Publ. 260-46 (March 1975). COM75-

10339**

Hust, J. G., Standard Reference Materials: Electrical Resistivity ofElectrolytic Iron, SRM 797, and Austenitic

Stainless Steel, SRM 798, from 5 to 280 K,NBS Spec.

Publ. 260-47 (February 1974). COM74-50176** Mangum, B. W., and Wise, J. A., Standard Reference

Materials: Description and Use of Precision Ther- mometers for the Clinical Laboratory, SRM 933 and SRM 934, NBS Spec. Publ. 260-48 (May 1974). COM74-50533**

Carpenter, B. S., and Reimer, G. M., Standard Reference

Materials: Calibrated Glass Standards for Fission Track Use, NBS Spec. Publ. 260-49 (November

1974). COM74-5 1185**

Hust, J. G., and Giarratano, P. J., Standard Reference

Materials: Thermal Conductivity and Electrical Resistivity Standard Reference Materials: Electro- lytic Iron, SRM's 734 and 797 from 4 to 1000 K, NBS

Spec. Publ. 260-50 (June 1975). COM75-10698**

Mavrodineanu, R., and Baldwin, J. R., Standard Refer- ence Materials: Glass Filters As a Standard Reference

Material for Spectrophotometry-Selection, Preparation, Certification, Use-SRM 930 NBS Spec. Publ. 260-51 (November 1975). COM75- 10339**

vi i
Hust, J. G., and Giarratano, P. J., Standard Reference

Materials: Thermal Conductivity and Electrical Resistivity Standard Reference Materials 730 and 799, from 4 to 3000 K, NBS Spec. Publ. 260-52 (September 1975). COM75-11193**

Durst, R. A., Standard Reference Materials: Standardization of pH Measurements, NBS Spec. Publ. 260-53 (February 1988, Revision of December 1975

version). Burke, R. W., and Mavrodineanu, R., Standard Refer- ence Materials: Certification and Use of Acidic Potassium Dichromate Solutions as an Ultraviolet Absorbance Standard, NBS Spec. Publ. 260-54

(August 1977). PB272 168**

Ditmars, D. A., Cezairliyan, A., Ishihara, S., and Douglas, T. B., Standard Reference Materials: Enthalpy and Heat Capacity; Molybdenum SRM 781, from 273

to 2800 K, NBS Spec. Publ. 260-55 (September 1977).PB272127**

Powell, R. L., Sparks, L. L., and Hust, J. G., Standard Reference Materials: Standard Thermocouple Material, Pt-67: SRM 1967, NBS Spec. Publ. 260-56 (Feb- ruary 1978). PB277 172**

Barnes, J. D., and Martin, G. M., Standard Reference

Materials: Polyester Film for Oxygen Gas Transmission Measurements SRM 1470, NBS Spec. Publ. 260- 58 (June 1979). PB297098**

Velapoldi, R. A., Paule, R. C, Schaffer, R., Mandel, J., and Moody, J. R., Standard Reference Materials: A

Reference Method for the Determination of Sodium

in Serum, NBS Spec. Publ. 260-60 (August 1978). PB286944**

Verdier, P H., and Wagner, H. L., Standard Reference

Materials: The Characterization of Linear Polyethylene (SRM 1482, 1483, 1484), NBS Spec. Publ. 260-

61 (December 1978). PB289899**

Soulen, R. J., and Dove, R. B., Standard Reference Materials: Temperature Reference Standard for Use Below

0.5 K (SRM 768), NBS Spec. Publ. 260-62 (April 1979).PB294245**

Velapoldi, R. A., Paule, R. C, Schaffer, R., Mandel, J., Machlan, L. A., and Gramlich, J. W., Standard Refer- ence Materials: A Reference Method for the Determination of Potassium in Serum, NBS Spec. Publ. 260-63 (May 1979). PB297207**

Velapoldi, R. A., and Mielenz, K. D., Standard Refer- ence Materials: A Fluorescence Standard Reference

Material Quinine Sulfate Dihydrate (SRM 936), NBS

Spec. Publ. 260-64 (January 1980). PB80-132046**

Marinenko, R. B., Heinrich, K. F. J., and Ruegg, F. C,

Standard Reference Materials: Micro-Homogeneity

Studies of NBS Standard Reference Materials, NBS

Research Materials, and Other Related Samples, NBS

Spec. Publ. 260-65 (September 1979). PB300461**

Venable, W. H, Jr., and Eckerle, K. L., Standard Refer- ence Materials: Didymium Glass Filters for Calibrat- ing the Wavelength Scale of Spectrophotometers-SRM 2009, 2010, 2013, and

2014, NBS Spec. Publ. 260-66 (October 1979). PB80-

104961**

Velapoldi, R. A., Paule, R. C, Schaffer, R., Mandel, J., Murphy, T. J., and Gramlich, J. W., Standard Refer- ence Materials: A Reference Method for the Determination of Chloride in Serum, NBS Spec. Publ. 260-67 (November 1979). PB80-110117**

Mavrodineanu, R., and Baldwin, J. R., Standard Refer- ence Materials: Metal-On-Quartz Filters as a Standard Reference Material for Spectrophotometry SRM

2031, NBS Spec. Publ. 260-68 (April 1980). PB80-

197486**

Velapoldi, R. A., Paule, R. C, Schaffer, R., Mandel, J., Machlan, L. A., Garner, E. L., and Rains, T. C, Standard Reference Materials: A Reference Method for the Determination of Lithium in Serum, NBS Spec. Publ. 260-69 (July 1980). PB80-209 117**

Marinenko, R. B., Biancaniello, F., Boyer, P. A., Ruff, A. W., and DeRobertis, L., Standard Reference Materials: Preparation and Characterization of an Iron- Chromium-Nickel Alloy for Microanalysis, NBS

Spec. Publ. 260-70 (May 1981). PB84-165349**

Seward, R. W., and Mavrodineanu, R., Standard Refer- ence Materials: Summary of the Clinical Laboratory

Standards Issued by the National Bureau of Standards, NBS Spec. Publ. 260-71 (November 1981). PB82-135161**

Reeder, D. J., Coxon, B., Enagonio, D., Christensen, R.

G., Schaffer, R., Howell, B. F., Paule, R. C, and Mandel, J., Standard Reference Materials: SRM 900, Antiepilepsy Drug Level Assay Standard, NBS Spec.

Publ. 260-72 (June 1981). PB81-220758

Interrante, C. G., and Hicho, G. E., Standard Reference

Materials: A Standard Reference Material Containing Nominally Fifteen Percent Austenite (SRM 486), NBS Spec. Publ. 260-73 (January 1982). PB82-

215559**

Marinenko, R. B., Standard Reference Materials: Preparation and Characterization of K-411 and K-414

Mineral Glasses for Microanalysis: SRM 470, NBS

Spec. Publ. 260-74 (April 1982). PB82-221300**

VI 11
Weidner, V. R., andHsia, J. J., Standard Reference Materials: Preparation and Calibration of First Surface Aluminum Mirror Specular Reflectance Standards (SRM 2003a), NBS Spec. Publ. 260-75 (May 1982). PB82-221367**

Hicho, G. E., and Eaton, E. E., Standard Reference Materials: A Standard Reference Material Containing Nominally Five Percent Austenite (SRM 485a), NBS

Spec. Publ. 260-76 (August 1982). PB83-1 15568** Furukawa, G. T., Riddle, J. L., Bigge, W. G., and Pfieffer, E. R., Standard Reference Materials: Application of Some Metal SRM's as Thermometric Fixed Points, NBS Spec. Publ. 260-77 (August 1982). PB83-

117325**

Hicho, G. E., and Eaton, E. E., Standard Reference Materials: Standard Reference Material Containing Nominally Thirty Percent Austenite (SRM 487), NBS

Spec. Publ. 260-78 (September 1982). PB83-

115576** Richmond, J. C, Hsia, J. J., Weidner, V. R., and Wilmering, D. B., Standard Reference Materials: Second Sur- face Mirror Standards of Specular Spectral

Reflectance (SRM's 2023, 2024, 2025), NBS Spec.

Publ. 260-79 (October 1982). PB84-203447**

Schaffer, R., Mandel, J., Sun, T., Cohen, A., and Hertz, H. S., Standard Reference Materials: Evaluation by

an ID/MS Method of the AACC Reference Method

for Serum Glucose, NBS Spec. Publ. 260-80 (October

1982). PB84-216894**

Burke, R. W., and Mavrodineanu, R., Standard Refer- ence Materials: Accuracy in Analytical Spectrophotometry, NBS Spec. Publ. 260-81 (April 1983). PB83-214536**

Weidner, V. R., Standard Reference Materials: White

Opal Glass Diffuse Spectral Reflectance Standards

for the Visible Spectrum (SRM's 2015 and 2016), NBS Spec. Publ. 260-82 (April 1983). PB83-

220723**

Bowers, G. N., Jr., Alvarez, R., Cali, J. P., Eberhardt, K.

R., Reeder, D. J., Schaffer, R., and Uriano, G. A., Standard Reference Materials: The Measurement of

the Catalytic (Activity) Concentration of Seven Enzymes in NBS Human Serum SRM 909, NBS

Spec. Publ. 260-83 (June 1983). PB83-239509**

Gills, T. E., Seward, R. W., Collins, R. J., and Webster, W. C, Standard Reference Materials: Sampling,

Materials Handling, Processing, and Packaging of NBS Sulfur in Coal Standard Reference Materials 2682, 2683, 2684, and 2685, NBS Spec. Publ. 260-84

(August 1983). PB84-109552**

Swyt, D. A., Standard Reference Materials: A Look at Techniques for the Dimensional Calibration of Standard Microscopic Particles, NBS Spec. Publ. 260-85

(September 1983). PB84-1 12648**

Hicho, G. E., and Eaton, E. E., Standard Reference Materials: A Standard Reference Material Containing Two

and One-Half Percent Austenite, SRM 488, NBS

Spec. Publ. 260-86 (December 1983). PB84-

143296** Mangum, B. W., Standard Reference Materials: SRM

1969: Rubidium Triple-Point - A Temperature Refer- ence Standard Near 39.30 °C, NBS Spec. Publ. 260- 87 (December 1983). PB84-149996**

Gladney, E. S., Burns, C. E., Perrin, D. R., Roelandts, I., and Gills, T. E., Standard Reference Materials: 1982

Compilation of Elemental Concentration Data for NBS Biological, Geological, and Environmental

Standard Reference Materials, NBS Spec. Publ. 260- 88 (March 1984). PB84-2 18338**

Hust, J. G., Standard Reference Materials: A Fine- Grained, Isotropic Graphite for Use as NBS Ther- mophysical Property RM's from 5 to 2500 K, NBS

Spec. Publ. 260-89 (September 1984). PB85-

112886**

Hust, J. G., and Lankford, A. B., Standard Reference

Materials: Update of Thermal Conductivity and Electrical Resistivity of Eleetrolytic Iron, Tungsten, and

Stainless Steel, NBS Spec. Publ. 260-90 (September

1984). PB85-1 15814**

Goodrich, L. F., Vecchia, D. F., Pittman, E. S., Ekin, J. W., and Clark, A. F., Standard Reference Materials:

Critical Current Measurements on an NbTi Superconducting Wire Standard Reference Material, NBS

Spec. Publ. 260-91 (September 1984). PB85-

118594**

Carpenter, B. S., Standard Reference Materials: Cali- brated Glass Standards for Fission Track Use (Supple- ment to NBS Spec. Publ. 260-49), NBS Spec. Publ. 260-92 (September 1984). PB85-1 13025**

Ehrstein, J.R., Standard Reference Materials: Preparation and Certification of Standard Reference Materials for Calibration of Spreading Resistance Probes, NBS Spec. Publ. 260-93 (January 1985). PB85-

177921**

Gills, T. E., Koch, W. F., S tolz, J. W., Kelly, W. R., Paulsen, P. J., Colbert, J. C, Kirklin, D. R., Pei, P.T.S., Weeks, S., Lindstrom, R. M., Fleming, R. F., Greenberg, R. R., and Paule, R. C, Standard Refer- ence Materials: Methods and Procedures Used at the National Bureau of Standards to Certify Sulfur in Coal SRM's for Sulfur Content, Calorific Value, Ash

Content, NBS Spec. Publ. 260-94 (December 1984). PB85-165900**

ix
Mulholland, G. W., Hartman, A. W., Hembree, G. G., Marx, E., and Lettieri, T. R., Standard Reference

Materials: Development of a 1 |im Diameter Particle Size Standard, SRM 1690, NBS Spec. Publ. 260-95 (May 1985). SN003-003-02665-4*

Carpenter, B. S., Gramlich, J. W., Greenberg, R. R., Machlan, L. A., DeBievre, P., Eschbach, H. L., Meyer, H., Van Audenhove, J., Connolly, V. E., Trahey, N. M., and Zook, A. C, Standard Reference

Materials: Uranium-235 Isotopic Abundance Standard Reference Materials for Gamma Spectrometry Measurements, NBS Spec. Publ. 260-96 (September

1986). PB87- 108544**

Mavrodineanu, R., and Gills, T. E., Standard Reference

Materials: Summary of the Coal, Ore, Mineral, Rock, and Refactory Standards Issued by the National Bureau of Standards, NBS Spec. Publ. 260-97 (Sep- tember 1985). SN003-003-02688-3*

Hust, J. G., Standard Reference Materials: Glass Fiber- board SRM for Thermal Resistance, NBS Spec. Publ. 260-98 (August 1985). SN003-003-02674-3*

Callanan, J. E., Sullivan, S . A., and Vecchia, D. F., Standard Reference Materials: Feasibility Study for the Development of Standards Using Differential Scanning Calorimetry, NBS Spec. Publ. 260-99 (August

1985). SN003-003-02675-1*

Taylor, J. K., Standard Reference Materials: Handbook

for SRM Users, NBS Spec. Publ. 260-100 (September 1985). PB86-1 10897** Mangum, B. W., Standard Reference Materials: SRM

1970, Succinonitrile Triple-Point Standard: A

Temperature Reference Standard Near 58.08 °C, NBS

Spec. Publ. 260-101 (March 1986). SN003-003-

02722-7*

Weidner, V. R., Mavrodineanu, R., Mielenz, K. D., Velapoldi, R. A., Eckerle, K. L., and Adams, B., Standard Reference Materials: Holmium Oxide Solution Wavelength Standard from 240 to 640 nm - SRM

2034, NBS Spec. Publ. 260-102 (July 1986). PB86-

245727**

Hust, J. G., Standard Reference Materials: Glass Fiber- blanket SRM for Thermal Resistance, NBS Spec.

Publ. 260-103 (September 1985). SN003-003-02687-

5* Mavrodineanu, R., and Alvarez, R., Standard Reference

Materials: Summary of the Biological and Botanical Standards Issued by the National Bureau of Standards, NBS Spec. Publ. 260-104 (November 1985). SN003-003-02704-9*

Mavrodineanu, R., and Rasberry, S. D., Standard Refer- ence Materials: Summary of the Environmental Research, Analysis, and Control Standards Issued by the National Bureau of Standards, NBS Spec. Publ. 260- 105 (March 1986). SN003-003-02725-1* Koch, W. F., ed., Standard Reference Materials: Methods and Procedures Used at the National Bureau

of Standards to Prepare, Analyze, and Certify SRM

2694, Simulated Rainwater, and Recommendations

for Use, NBS Spec. Publ. 260-106 (July 1986). PB86-

247483**

Hartman, A. W., and McKenzie, R. L., Standard Refer- ence Materials: SRM 1965, Microsphere Slide (10 Urn Polystyrene Spheres), NBS Spec. Publ. 260-107 (November 1988). Mavrodineanu, R., and Gills, T. E., Standard Reference

Materials: Summary of Gas Cylinder and Permeation Tube Standard Reference Materials Issued by the National Bureau of Standards, NBS Spec. Publ. 260- 108 (May 1987). Candela, G. A., Chandler-Horowitz, D., Novotny, D. B., Marchiando, J. F., and Belzer, B. J., Standard Refer- ence Materials: Preparation and Certification of an El- lipsometrically Derived Thickness and Refractive Index Standard of a Silicon Dioxide Film (SRM

2530), NIST Spec. Publ. 260-109 (October 1988). Kirby, R. K., and Kanare, H. M., Standard Reference

Materials: Portland Cement Chemical Composition

Standards (Blending, Packaging, and Testing), NBS

Spec. Publ. 260-110 (February 1988). Gladney, E. S., O'Malley, B. T., Roelandts, I., and Gills, T. E., Standard Reference Materials: Compilation of Elemental Concentration Data for NBS Clinical, Biological, Geological, and Environmental Standard Reference Materials, NBS Spec. Publ. 260-111 (November 1987). *Send order with remittance to Superintendent of Documents, U.S . Government Printing Office, Washington, DC 20102. Remittance from foreign countries should include an additional one fourth of the pur- chase price for postage. **May be ordered from: National Technical Information Services (NTIS), Springfield, VA 22161.

X
GLASSES FOR MICROANALYSIS: SRM'S 1871-1875

R. B. Marinenko, Center for Analytical Chemistry D. H. Blackburn, Instititute of Materials Science and Engineering

National Institute of Standards and Technology

Gaithersburg, Maryland 20899

and

J. B. Bodkin, Mineral Constitution Laboratories The Pennsylvania State University

University Park, Pennsylvania 16802 INTRODUCTION

Glass is an ideal material for multielement microanalytical standards. Over 60 elements can be used in making glasses and as many as 20 or more elements can be incorporated into a single glass. Oxide glasses generally exhibit excellent chemical and physical stability as well as structureless homogeneity. A glass matrix was therefore chosen for making this group of microanalytical standards which spans a wide range of average atomic numbers

with many other oxides as minor constituents. The preparation, homogeneity testing, and quantitative analyses of the Glasses for Microanalysis, Standard Reference Materials (SRM's) 1871 - 1875 are described. Each

SRM represents a different glass matrix; these are lead-silicate (SRM 1871), lead- germanate (SRM 1872), barium-zinc-silicate (SRM 1873), lithium-aluminum-borate (SRM

1874), and aluminum-magnesium-phosphate (SRM 1875). There are three glasses in each SRM, one composed only of the matrix oxides and the other two having small additions

(less than two percent) of several other elements in oxide form. The certified compositions, information values (non-certified compositions), and nominal values (amount of weighed material added to the melt during preparation) are listed in tables 1-5. PREPARATION

The glasses were made at the National Institute of Standards and Technology (NIST)

by D. H. Blackburn and D. A. Kauffman, Inorganic Materials Division, Center for Materials Science and Engineering. The chemicals used were reagent grade materials or compounds of equal or greater purity. In most preparations, stable oxides were used, but where this was not possible, carbonates, nitrates, and phosphates, which decompose to the appropriate oxides in the glass-melting process, were used. The batch materials were well- mixed as dry powders prior to melting. Each glass was melted in a 300 mL platinum

crucible and stirred with a motor-driven platinum-rhodium alloy propeller-type stirrer. Melting and stirring operations were performed in electrically heated furnaces in an

oxidizing atmosphere (air). Temperatures ranged from below 1000 °C to above 1500 °C

depending upon the glass being prepared. All glasses were stirred 4 to 6 hours to insure homogeneity. After stirring, the molten glass was cast into a rectangular block and

annealed for half an hour to remove residual strain. The mold had an aluminum bottom and

stainless steel sides. Details about the preparation of each glass matrix are discussed below.

1
Lead-Silicate Glasses. K-456, K-493. and K-523 : Silicon dioxide makes an excellent

glass, but without modifications, the glass has a high melting temperature and the molten

glass is extremely viscous. Lead oxide was selected as a modifier because it lowers both

the melting temperature and the viscosity without sacrificing glass stability. These glasses were melted, stirred, and poured in the 1290-1320 °C temperature range and annealed at 480 °C. Lead-Germanate Glasses. K-453. K-491. and K-968 : Germanium dioxide also makes

a glass when cooled from a melt, but even at 1600 °C is extremely viscous. The resulting glass is also not stable in the presence of water vapor. Lead oxide lowers the viscosity and improves the moisture stability. The glasses were processed in the 980-1010 °C

temperature range and annealed at 400 °C. Barium-Zinc-Silicate Glasses. K-458. K-489. and K-963 : Barium oxide lowers the melting temperature and viscosity of the silicon dioxide, but barium-silicate glasses exhibit sub-liquidus phase separation due to metastable immiscibility. Small additions of zinc oxide

prevent the immiscibility and resulting inhomogeneity. Processing temperatures for these

glasses were from 1500-1540 °C, and the glasses were annealed at 680 °C. Lithium-Aluminum-Borate Glasses. K-495. K-490. and K-546: Boron oxide, without

modification, makes a glass which is not stable in the presence of water vapor. The

addition of lithium oxide serves a dual purpose. It improves moisture stability and

increases the solubility of other oxides in the resulting glass. Aluminum oxide additions

further improve durability against moisture. The glasses were melted, stirred, and poured

between 1050 and 1 100 °C and annealed at 525 °C. Aluminum-Magnesium-Phosphate Glasses. K-496. K-497, and K-1013 : Phosphorus

pentoxide is a glass-former, but under normal pressure sublimes rather than melts when

heated. It is also water-soluble and extremely hygroscopic. Aluminum metaphosphate,

A1(PC>3)3, however, makes a very stable glass that is not affected by moisture even though

it contains a high percentage of phosphorus pentoxide. Additions of magnesium

phosphate, Mg(P03)2 were made to lower both the melting temperature and viscosity without sacrificing moisture resistance. The glasses were processed in the 1380-1420 °C

temperature range and were annealed at 620 °C. The SRM specimens were cut from each glass block using a precision wafering saw

with a 0.07 x 15.2 cm (0.028 x 6") 100-grit diamond wheel and a petroleum-based

solvent. Each bar was cut into several hundred rod-like pieces approximately 2 x 2 x 20 mm. From the final lot, specimens were randomly selected for wet chemical analysis. Each rod was broken in half, one half to be submitted for the wet chemical analysis and the remaining half to be retained at NIST for future reference or for additional analyses if needed. Three grams of sample per element determination were submitted for quantitative

analysis. This quantity provided enough sample for triplicate determination of each oxide. Five or six additional rods were randomly selected from the lot and mounted with standards

in silver epoxy in a titanium sample mount for x-ray microanalysis. The sample mounts

were polished with diamond polishing compound and cerium oxide and then carbon-coated

for microprobe analysis. HOMOGENEITY

The micro- and macrohomogeneity (between-specimen homogeneity) of the major

constituents in each glass were determined by R. Marinenko with the electron microprobe

according to the procedures described in references (1) and (2). The transverse microhomogeneity was observed with periodic integrator traces (1) such as those in figures

1 to 4. Here the specimen was moved in l-|j.m steps under a l-|im diameter electron beam. In all cases these traces gave signals that were within the ±3s limits delineated by the double-headed arrow to the extreme right of each trace, where s is Vn and N is the average number of counts per 10-second counting period for the trace. Also each trace of the moving specimen appeared to be the same as the time-resolved trace to the left in each

2
figure which was recorded with a 20-|am electron beam on a stationary specimen.

Experience with statistical analyses of traces such as these has shown that when the visual

criteria cited above are met in a periodic integrator trace, there are no inhomogeneities of

practical significance (1,2). Periodic integrator traces of aluminum in the glasses in SRM 1 874 exhibited a drift, regardless of the current used. This is not necessarily because aluminum is inhomogeneous in these glasses; the homogeneity of aluminum will be demonstrated below

in another test. Rather, the drift may be due in part to a loss of components caused by

electron beam damage to the specimen. These glasses do not hold up well under the electron beam - obvious damage can be seen even with a defocussed beam at the lowest

currents. When the beam is moved randomly over large distances from one spot to another

as was done in the following experiment, these glasses are subject to less damage than in the preparation of periodic integrator traces where each point is adjacent to the previous

one. Also, the presence of lithium, which is known to migrate under the electron beam,

could contribute to the difficulty in analyzing these glasses. Since these glasses were

originally intended for use in Secondary Ion Mass Spectrometry (SIMS) analysis and not

electron probe microanalysis (EPMA), such problems were not pursued further. In the homogeneity tests and quantitative analysis of SRM 1874 which will be

described below, EPMA was used successfully. These analyses were conducted very

carefully in an effort to obtain as much information as possible about these glasses for

certification purposes. Use of these standards in routine quantitative EPMA work is discouraged. Because of the low atomic number matrices, these standards are far better suited as standards for SIMS analyses. A second homogeneity testing procedure (2) was used to evaluate statistically both the inter-specimen macrohomogeneity as well as the within-specimen microhomogeneity.

Duplicate readings were taken on six randomly selected points of five specimens and each specimen was randomly sampled twice in the experiment. This results in a total of 120

readings per experiment, two on each of 60 different points. Another sampling procedure was later adopted. It improves the randomness of the

inter- and intra- specimen sampling, minimizing the effects of beam current drift during the experiment. In the second sampling procedure, only two points (with duplicate readings on each) are sampled per specimen before moving on to the next specimen. The five specimens are thus sampled in random order six times, again giving a total of 120 readings, two on each of 60 points. In tables 6-10 where the results of these homogeneity tests are tabulated, experiments K-453D and K-491G and H were done with the second sampling

procedure. But in experiments K-496C, K-497C, and K-1013F only one point was read

twice before proceeding to the next specimen. For all homogeneity tests, three crystal spectrometers were used. When there were only two major components in a glass, duplicate data were taken for one of the elements with the

third spectrometer. The excitation potential chosen depended upon the element being

tested. The beam current was within the range of 30-40 nA. The beam current regulation

mode was used to minimize current drift during each experiment, which lasted about 1 1/2 hours. At least duplicate tests were run on each glass. These were prepared on different days and, when possible, by different operators. Counting periods were 20 s. A point

beam (less than 1 |im diameter) was used for SRM's 1871-1873. The glasses in SRM's

1874 and 1875 were more difficult to analyze because of beam damage to the specimens.

Several experiments were run to check for damage to these glasses at different beam sizes, beam currents, and counting times. A 10 x 10 urn scanning raster minimized the beam

damage to the specimens within the 20 s counting period at the selected beam current. Adequate counting statistics without drift during the counting time could be obtained under

these conditions. In addition this beam size was not so large as to cause defocusing outside

the optimum detection range of the spectrometers. The use of the same beam size is recommended when using these specimens as standards in WDS analyses. With the lower

currents used in EDS analyses, a point beam may be used. 3
Three different error contributions can be estimated from this testing procedure. They

are ss

2

, the variance between specimens, sb

2

, the variance within specimens on the micrometer scale, and Se

2

', the variance of a single measurement error. These errors are described in detail in reference 2. They are tabulated for each experiment in tables 6 to 10. The errors for the glasses in SRM's 1871-3 are generally lower than the errors for the glasses in SRM's 1874-5. This does not necessarily mean that the former are more

homogeneous. The difference is attributable to the greater difficulty in testing the latter, where high counting statistics were not practical because of specimen damage at high

currents. With very few exceptions, the error between points within a given specimen, sb, is below one percent as shown in the tables. This information in combination with the periodic integrator traces confirms that these glasses show no practical within-specimen

inhomogeneity on the micrometer scale. The experimental standard deviation, se, is estimated from the net number of counts per counting period; therefore, the higher the number of integrated counts, the lower will be

this error. Only for zinc in SRM 1873 and for aluminum in SRM 1874 is this error as high

as one percent relative. For each element, the integrated number of counts per 20 s was

only 10,000. The between-specimens standard deviation, ss, is generally well below one percent; in the experiments where it does exceed one percent, the error is not consistent from one

experiment to another on the same glass. Only for magnesium in K-1013 of SRM 1875 is there a consistently large between-specimen error. With this one exception, no betweenspecimen inhomogeneity of any practical significance can be inferred. The standard deviation of a single measurement, sp, is defined below according to the equation

S P

2 = SE2 + SB2 + SS 2

. The values for sp are listed in the extreme right column of each table. For the glasses in SRM's 1871-3, these errors are small. The major elements in these glasses show no

inhomogeneity of any practical significance. These errors for SRM's 1874 and 1875 are

slightly larger. Therefore an inhomogeneity error was calculated and combined with the

quantitative analysis error to obtain the final uncertainties quoted in the certificates. The inhomogeneity error, 2si was calculated for a single point. For each element in each experiment the between-points and between-specimen errors were combined

according to the expression

2si

2 = sB2 + ss2

. For each element an average value for 2si is calculated from the different experiments on

each glass. This average value is then combined in quadrature with the quantitative

analysis error (two standard deviations from the average) to obtain the uncertainty listed with the certified value. Quantitative Analysis Most of the major constituents of each glass, with the exception of oxygen, were

quantitatively determined by wet chemical analysis and EPMA. Silicon in glasses K-456

and K-453 was determined by emission spectrometry; inductively coupled plasma (ICP) spectrometry was used for K-456, and ICP and direct current plasma (DCP) spectrometry were used for K-453. Zinc in glass K-458 of SRM 1873 and aluminum in all three glasses of SRM 1875 were determined by neutron activation. Aluminum in glasses K-490 and K- 546 of SRM 1874 and in K-497 and K-1013 of SRM 1875 was not determined by wet

chemistry because several of the dopant elements in these glasses interfere with aluminum

determinations. Lithium and boron in the glasses of SRM 1874 were not determined with 4
EPMA because accurate quantitative results for these elements could not be obtained with our present instrumentation. The individual results from each analytical procedure are listed in tables 1 1-15. These results are plotted for each element in figures 5-9. The certified value for each major constituent (tables 1-5 and 11-15) was determined from the weighted average of the results from the two or three different analytical

procedures. This weighted average was calculated according to the method described by

Paule and Mandel (3). The error cited is ±2s, which for all elements but barium in glass K963 is two times the pooled standard deviation of the certified value. The pooled value was

determined from all three glasses in each SRM, and for aluminum it was taken from the three glasses in SRM 1875 plus K-495 in SRM 1874. For barium in SRM 1873 this error was calculated differently because the standard deviation for barium in glass K-963 was more than twice that of the other two glasses in this SRM. Therefore, a pooled value

(±.20) was used for K-458 and K-489 while a single value (±.48) was used for K-963. For glasses K-493 and K-523 in SRM 1871 (table 1) and K-489 and K-963 in SRM 1873

(table 2) the silicon values (in parentheses) are not certified and are provided for information only. Also, only information values (in parentheses) are provided for aluminum in glasses K-490 and K-546 of SRM 1874 as well as for lithium and boron in all three glasses of this SRM. These information values have no errors reported because they were calculated from the average of repeated analyses by only one method. These elements

will have to be determined by a second analytical procedure for final certification. Most of the minor elements were determined with EPMA, and tantalum in four glasses was determined with neutron activation. Lithium and boron also were not determined with EPMA, so only nominal values are reported. The results are also listed in tables 1-5 and

are compared to the nominal values in brackets. ELECTRON MICROPROBE

The major and minor constituents were quantitatively determined by R. Marinenko with wavelength dispersive spectrometry (WDS). The voltages and standards used in the determination of each element are listed in table 16. For most glasses, a point beam (less than 1 fim) was used, but when beam damage on the specimen was a problem, a 10 x 10

u.m scanning raster was used. Five or six randomly selected points were sampled on the standards, the glasses, and the background specimens. Results were averaged and

background-corrected, then k-ratios were calculated for data reduction with either FRAME

(4) or COR (5). In all quantitative analyses the beam current was monitored intermittently throughout each experiment with a Faraday cup. With the current regulator, the beam current showed

little or no drift (usually much less than one percent). For the major constituents each glass was analyzed in three different experiments. As previously mentioned the results of the analyses are listed in tables 11-15 and the individual values are plotted in figures 5-9. The

EPMA values for the minor components are in most cases in good agreement with the nominal values; but since these elements occur in amounts so close to the lower limit of

detection of the electron microprobe, a significant error is associated with these

determinations. Therefore, the EPMA values are being provided for information only. The combination of matrix elements in each of these SRM's had not been determined in our laboratory before these studies. There were some limitations on the excitation potential and current that could safely be used in the analyses of these SRM's without affecting the composition of the glass specimens. Below is a brief description of the problems or special considerations associated with the analysis of each SRM.

SRM 1871. Lead-silicate glasses . Some errors were observed in the silicon determinations using both FRAME and COR data reduction procedures. When quartz (Si02) and the mineral glass K-411 (SRM 470) were used as standards, the calculated

silicon concentration was consistently several percent higher than expected. Also the

analytical total exceeded 100 percent, confirming that at least one of the elements in the

5
glasses was being calculated too high. These two standards have an average atomic number of 1 1 or below while the average atomic number of the lead-silicate glasses is about

56. Benitoite (BaTiSi309) with an average atomic number of 27, turned out to be a better standard, although the silicon results were still somewhat high. There is probably an atomic number effect from lead which is not entirely accounted for in our data reduction procedures. The best standard proved to be another NIST lead- silicate glass, K-227,

which we have used successfully in our laboratory for many years. The nominal values, wet chemistry results, and electron microprobe results for this glass are shown in table 17. Because of the good agreement between the electron microprobe and the wet chemistry

analyses, the average value from the latter analyses was used for this standard in the data

reduction calculations. An excitation potential of 15 kV was used. SRM 1872, Lead-germanate glasses. This combination of elements was also new to

us. Analysis is straightforward as long as COR is used for matrix corrections. The

germanium K line is excited by the lead L lines. For simplicity, the correction for this fluorescence, which is usually very small or insignificant, is not present in the FRAME

program. Without the fluorescence correction, the calculated germanium concentration was

as much as three percent above the expected concentration. The standards used were K227 (Pb) and germanium. A 15 kV excitation potential was used. SRM 1873. Barium-zinc- silicate glasses . The analysis of these glasses was

straightforward. Both FRAME and COR gave the same results. The standards were

Benitoite (Ba), K-227 (Si), and zinc. The excitation potential was 15 kV. One of the minor

constituents was not determined. This was cerium in glass K-489. The barium La peak,

which is close to the cerium La peak, contributes a considerable background under the cerium peak. Because of the low cerium concentration, the La peak cannot be resolved above the barium background.

SRM 1874. Lithium-aluminum-borate glasses . Because of the low average atomic number of these glasses, the current had to be maintained low enough (below 15 nA) to avoid damage to the specimen during the counting time. A 10 x 10 mm scanning raster was

also used to minimize specimen damage. An optimum current with this beam size which would give the best possible counting statistics for aluminum without showing any change

in the count rate during the 40-s counting period was experimentally determined. COR was

used for data reduction; lithium and boron were treated as knowns, using concentrations

for these elements that had been determined by wet chemistry. The standard was aluminum

oxide.SRM 1875. Aluminum-magnesium-phosphate glasses . The low average atomic number of these glasses presented the same problem cited above in the analysis of SRM

1874. A 10 x 10 mm scanning raster again was used to minimize specimen damage, and

the current was carefully selected (50 nA or below) to prevent count rate drift during

analyses. The excitation potential was 10 kV. The standard for aluminum and magnesium

was glass K-412 (SRM 470), and for phosphorus, apatite was used. COR was used for data reduction. WET CHEMISTRY

The quantitative wet chemical analyses were done in the Mineral Constitution

Laboratories at The Pennsylvania State University by Joseph B. Bodkin and co-workers under the direction of Dr. Norman H. Suhr. Only the major constituents were determined

for certification. The procedures used are listed in table 18. The results are listed in tables 11-15 and plotted in figures 5-9. EMISSION SPECTROMETRY

Emission spectrometry analyses were done in the Inorganic Analytical Research

Division, NIST. The ICP spectrometry was done by R. L. Watters and the DCP

spectrometry by M. S. Epstein. For ICP analysis, duplicate specimens were fused with 6
sodium carbonate, dissolved in water and brought to volume. Lead precipitation from the K-456 sample was prevented by the addition of about 2 g/L tartaric acid. Two silicon standards were prepared to match the sodium carbonate content of the samples. The

concentration value reported for each specimen is the average of four ICP integrations. For DCP spectrometry the specimens were fused with lithium borate, dissolved in dilute hydrochloric acid, and brought to volume. Standards were prepared with the same

lithium concentration as the specimens. At least four 10-s integrations were taken per specimen. These were averaged for the final value reported. Data are listed in tables 1

1

and 13 and plotted in figures 5 and 7. NEUTRON ACTIVATION

Neutron Activation Analysis was done by R. M. Lindstrom and G. J. Lutz of the Inorganic Analytical Research Division, NIST. The determination of aluminum in the SRM 1875 glasses was done at the NIST reactor facility. To avoid interference from the fast-neutron reaction on phosphorus, the samples were irradiated in the thermal-column

facility RT5 at a flux of 1.6 x 1011 n/cm2

s. Five samples of each glass, standards of pure aluminum wire, check standards, and blanks were irradiated singly for 2 minutes and

counted on the ATF detector at 20-cm geometry. The PEAK program was used to integrate the Al-28 peak. Corrections were made for decay, dead time, and pulse pileup. Irradiation of K2HPO4 showed that the fast-neutron reaction contributed an apparent aluminum concentration of less than 0.002 grams of aluminum per gram of glass containing 75 percent P2O5, at the 95 percent confidence level. Analysis of SRM 120a Phosphate Rock (34.4 percent P2O5) for aluminum confirmed the absence of phosphorus

interferences; SRM 1633a Fly Ash was analyzed to verify the procedure. Three

determinations of aluminum in SRM 1633a, Fly Ash, gave 14.4±0.3 percent aluminum. A

previous determination of aluminum in SRM 1633a gave 14.1±0.1 percent. The determinations of tantalum and zinc were done at the University of Missouri Research Reactor. Specimens were irradiated for 5 minutes at a flux of 5 x 10 13 n/cm2

-s. Because of a 15 percent flux gradient from side to side in the rabbit at this facility, a zinc

flux monitor was taped to each packaged specimen. A solution of tantalum was used as a tantalum standard, and high purity zinc metal was used as a standard in the zinc

determination. The nuclear reactions and gamma-rays used in the analysis were:

Tantalum was determined in glasses K-493, K-491, K-489, and K-497. Zinc was

determined in glass K-458. Attempts to determine Zn in glass K-489 were unsuccessful because of interferences from the 1.113 and 1.121 Mev lines of 182Ta. Efforts to strip the tantalum component from the spectrum of this glass were also unsuccessful. NEUTRON DEPTH PROFILING Boron depletion is known to occur at the surface of boron- containing glasses when

exposed to an aqueous environment (6). This depletion occurs because of the formation and dissolution of boric acid when the specimen comes into contact with water. All of

these SRM glass specimens had been in an aqueous environment during cutting and

polishing. Neutron depth profiling (NDP) was therefore done on specimens K-490, K495, and K-546 to determine the extent of depletion. The analysis was done by R. G. Downing (7) of the Inorganic Analytical Research Division, NIST. For each glass, a region about 1 cm in diameter was studied. Observation of the emission of 1472.3 keV alpha particles from the 10B(n,a)7Li reaction showed that there is

181'Ta(n,g) 182Ta

l Zn(n,g) 65Zn

1.121 Mev

1.115 Mev. 64'

7
indeed boron depletion near the surface. Relative to the bulk concentration observed at 1.5 mm in depth, the specimens were found to be 20-30 percent boron- depleted at 0.12 mm

with depletion dropping to 3-7 percent at 0.5 mm; no depletion was observed beyond 1.3 mm.A Monte Carlo calculation (8) was run to determine the depth from which x rays are generated in a specimen with the composition of glass K-495 at an excitation potential of 10 kV. This type of calculation is used to theoretically predict what physical interactions occur

in a specimen of given composition when excited by an electron beam. Each electron event

is calculated individually. For these studies, 10,000 trajectories were calculated. The results of these calculations showed that aluminum x-rays are generated from a depth of up to 1 .3 mm. If boron depletion effectively led to aluminum enrichment, the amount of generated aluminum x-rays would increase by one-third. One would expect from

these results that electron microprobe analysis of K-495 would yield a much higher

concentration of aluminum than was determined by wet chemistry. This, in fact, does not occur as can be seen in table 14, where wet chemistry and the EPMA results are in very good agreement. It appears, therefore, that the loss of boron has not meant that aluminum

has, in part, filled the void. Probably another replacement, such as water, has occurred or

the voids have remained unfilled. Because of this boron depletion on the surface as well as the presence of lithium, which

is known to migrate under the electron beam, the use of these glasses (SRM 1874) for

quantitative EPMA is not recommended. This SRM is most useful in SIMS analysis where

surface depletion is less of a problem because of the possibility of using ion beam erosion

to remove the altered layer. A freshly cleaved surface should be used to avoid as much as possible the loss of boron from the surface. CONCLUSIONS

These SRM's are unique microanalytical standards. The matrices are unusual combinations of oxides not found in presently available standards for microanalysis. The

major components show no serious inhomogeneities on the micrometer scale. And the additional low-concentration oxides (dopants), though not certified for either microhomogeneity or composition, are useful when a measurement reference at these concentration levels are needed. Acknowledgments

The authors wish to acknowledge K. F. J. Heinrich, formerly Group Leader of the Microanalysis Group, Center for Analytical Chemistry, NIST. His leadership in the development of these glasses for eventual certification was invaluable. Without his contributions, this long-term project would not have been accomplished. The authors wish

also to thank those associates cited in the text for their analytical contributions to the

certification of these SRM's and P. Sheridan, formerly of the Gas and Particulate Science

Division, NIST, for his assistance in taking homogeneity data. Thanks also to R. L. Myklebust of the Gas and Particulate Science Division, NIST, for his useful suggestions in the quantitative EPMA work. The authors also wish to thank Dr. R. Paule of the National Measurement Laboratory, NIST, for his assistance in calculating the certification values and in evaluating the homogeneity test data. Thanks also to R. W. Seward of the Office of Standard Reference Materials, NIST, for his assistance in preparing the certification for these SRM's and to D. E. Newbury, Group Leader of the Microanalysis Group, for his valued leadership and advice in completion of this project.

5
Table 1. SRM 1871, Lead-Silicate Glasses

Concentrations in Weight Percent Element Glass K-456 K-493 K-523

Pb 65.67 ±0.26 63.28 ± 0.26 63.10 ±0.26

Si 13.37 ±0.24 (13.09 ± 0.24) (12.94 ± 0.24) O (20.35) (20.58) (20.80)

Li [0.0005] B [0.04] Mg (0.12)[0.10] Al (0.13)[0.11] P (0.24)[0.25]

Ti (0.20)[0.19] (0.21)[0.19] Cr (0.20)[0.21] Fe (0.25)[0.22] Ni (0.25)[0.24] Ge (0.20)[0.29] Zr (0.38)[0.36] (0.33)[0.36] Ba (0.61)[0.55] Ce (0.53)[0.55] Eu (0.73)[0.60] Ta (0.64)[0.72]* Th (0.08)[0.10] U (0.23)[0.11]

Total (99.38) (99.12) (100.19) Values in parentheses are not certified and are provided for Information Only; values

' brackets are nominal values and are not certified. Concentration by neutron activation analysis for Ta = (0.74)

9
Table 2. SRM 1872, Lead-Germanate Glasses

Concentrations in Weight Percent Element Glass K-453 K-491 K-968

Pb 54.21 ± 0.26 54.69 ± 0.26 54.74 ± 0.26 Ge 28.43 ±0.34 26.10 ±0.34 25.93 ± 0.34 O (16.73) (16.45) (16.67)

li [0.0005] B [0.03] Mg (0.22)[0.08] Al (0.10)[0.09]

Si (0.11)[0.09] P (0.21)[0.20]

Ti (0.14)[0.16] (0.16)[0.16] Cr (0.1 9) [0.17] Fe (0.17)[0.18] Ni 0.20)[0.19] Zr (0.26)[0.30] (0.48)[0.30] Ba (0.46)[0.45] Ce (0.59)[0.46] Eu (0.64)[0.49] Ta (0.52)[0.59]* Th (0.12)[0.08] U (0.05)[0.09]

Total (99.37) (99.16) (100.07) Values in parentheses are not certified and are provided for Information Only; values in brackets are nominal values and are not certified. * Concentration by neutron activation analysis for Ta = (0.58)

1 0
Table 3. SRM 1873, Barium-Zinc-Silicate Glasses

Concentrations in Weight Percent Element Glasses K-458 K-489 K-963 Ba 41.79 ± 0.20 39.53 ± 0.20 39.21 ± 0.48 Zn 3.01 ± 0.06 2.93 ± 0.06 2.95 ± 0.06

Si 23.05 ±0.34 (22.23 ± 0.34) (21.9610.34)

O (31.86) (31.70) (32.00)

Li [0.0009] B [0.06] Mg (0.34)[0.14] Al (0.11)[0.15] P (0.33)[0.36]

Ti (0.27)[0.28] (0.32)[0.36] Cr (0.31)[0.30] Fe (0.35)[0.32] Ni (0.33)[0.34] Ge (0.47)[0.42] Zr (0.40)[0.52] (0.61)[0.53] Ce [0.80] Eu (0.95)[0.88] Ta (0.95)[1.03]* Pb (1.32)[1.19] Th (0.06)[0.13] U (0.16)[0.17]

Total (99.71) (100.65) (100.00) Values in parentheses are not certified and are provided for Information Only; values

brackets are nominal values and are not certified. * Concentration by neutron activation analysis for Ta = (1.03)

1 1
Table 4. SRM 1 874, Lithium-Aluminum-Borate Glasses

Concentrations in Weight Percent Element Glass K-495 K-490 K-546

li (2.33) (2.22) (2.16) Al 10.89 ± 0.23 (10.15) (10.06) B (22.97 (21.48) (21.62) O (63.39) (60.74) (60.75) Mg (0.17)[0.17]

Si (0.19)[0.20]

Jr \\)AA)\\jA5\

Ti (0.31)[0.33] (0.39)[0.34] Cr (0.1 5) [0.1 6] Fe (0.38)[0.38] Ni (0.39)[0.41] Ge (0.50)[0.51] Zr (0.53)[0.63] (0.52)[0.64] Ba (0.99)[0.96] Ce (1.46)[0.97] Eu (1.21)[1.06] Ta (1.02)[1.25] Pb (1.47)[1.44] Th (0.1 6) [0.1 61 U (0.24)[0.20]

Total (99.58) (99.49) (99.52) Values in parentheses are not certified and are provided for Information Only; values in brackets are nominal values and are not certified.

1 2
Table 5. SRM 1875, Aluminum-Magnesium Phosphate Glasses

Concentrations in Weight Percent Element Glass K-496 K-497 K-1013

Al 6.47 ± 0.20 5.97 + 0.22 6.08 ± 0.21 Mg 6.65 ±0.17 6.49 ±0.17 5.86 ± 0.26 P 32.98 ±0.55 31.59 ±0.58 32.26 ± 0.56 O (53.90)* (51.30)* (52.37)*

Li [0.0005] B [0.05]

Si (0.13)[0.13]

Ti (0.22)[0.21] (0.21)[0.22] Cr (0.14)[0.23] Fe (0.26)[0.24] Ni (0.31)[0.26] Ge (0.25)[0.33] Zr (0.32)[0.40] (0.45)[0.41] Ba (0.52)[0.61] Ce (0.94)[0.62] Eu (0.53)[0.67] Ta (0.71)[0.80]** Pb (0.86)[0.92] Th (0.10)[0.11] U (0.15)[0.13] Values in parentheses are not certified and are provided for Information Only; values in brackets are nominal values and are not certified. *Oxygen values calculated by difference because the stoichiometry of the phosphorus

oxides in these glasses is unpredictable **Concentration by neutron activation analysis forTa = (0.83)

13
Table 6. Homogeneity Evaluation of Glasses K-456, K-493, and K-5233

Standard Deviations in Weight Percent0 Glass Exp Element Wt. %b se SB ss sP K-456 A Si 13.37 0.04(0.30) 0.06(0.45) 0.02(0.10) 0.07(0.52) Pb 65.67 0.32(0.49) 0.68(1.03) 0^19(0^29) 0/77(L17)

Si 13.37 0.04(0.30) 0.05(0.26) 0.02(0.10) 0.06(0.44) B Si 13.37 0.04(0.30) 0.03(0.22) 0.03(0.22) 0.06(0.45) Pb 65.67 0.32(0.49) 0.10(0.15) 0.0 034(0*52)

Si 13.37 0.04(0.30) 0.02(0.15) 0.01(0.07) 0.05(0.37) K-493 B Si r 13 091 0.03(0.23) 0.03(0.23) 0.01(0.07) 0.04(0.31) Pb 63.28 0.32(0.50) 0.17(0.27) 0.06(0.09) 0.36(0.57)

Si [13.09] 0.03(0.23) 0.03(0.23) 0.0 0.09(0.33) C Si [13.09] 0.04(0.31) 0.03(0.22) 0.03(0.22) 0.06(0.45) Pb 63.28 0.32(0.51) 0.39(0.62) 0.24(0.38) 0.56(0.88)

Si [13.09] 0.04(0.31) 0.04(0.31) 0.02(0.15) 0.06(0.45) K-523 A Si [12.94] 0.03(0.23) 0.01(0.08) 0.01(0.08) 0.04(0.31) Pb 63.10 0.32(0.50) 0.0 0.09(0.15) 0.32(0.51)

Si [12.94] 0.03(0.23) 0.03(0.22) 0.05(0.18) 0.05(0.39) B Si [12.94] 0.04(0.31) 0.02(0.15) 0.01(0.08) 0.04(0.31) Pb 63.10 0.32(0.51) 0.29(0.46) 0.07(0.11) 0.44(0.70)

Si [12.94] 0.04(0.31) 0.06(0.46) 0.01(0.08) 0.07(0.54)

a 15 kV excitation potential and five specimens of each glass. bCertified concentrations; numbers in brackets are not certified and are provided for Information Only.

cValues in parentheses are relative errors in percent.

14
Table 7. Homogeneity Evaluation of Glasses K-453, K-491, and K-968a

Standard Deviations in Weight Percent0 Glass Exp Element Wt. %b Sp Sr Ss Sp K-453 A Pb 54.21 0.35(0.64) 0.34(0.63) 0.0 0.49(0.90) Pb 54.21 0.24(0.44) 0.29(0.53) 0.0 0.37(0.69) Ge 28.43 0.15(0.53) 0.03(0.12) 0.12(0.44) 0.19(0.67) D Pb 54.21 0.33(0.61) 0.10(0.18) 0.0 0.34(0.64) Pb 54.21 0.24(0.44) 0.13(0.24) 0.03(0.06) 0.27(0.51) Ge 28.43 0.14(0.49) 0.01(0.04) 0.03(0.11) 0.14(0.50) K-491 G Pb 54.69 0.33(0.60) 0.0 0.08(0.14) 0.34(0.62) Pb 54.69 0.24(0.44) 0.08(0.15) 0.06(0.11) 0.26(0.48) Ge 26.10 a i o / r\ cf\\ 0.13(0.50) 0.0 0.0 0.13(0.50) H Pb 54.69 0.33(0.60) 0.13(0.24) 0.0 0.35(0.64) Pb 54.69 0.24(0.44) 0.16(0.29) 0.03(0.05) 0.29(0.55) Ge 26.10 0.13(0.50) 0.02(0.08) 0.06(0.23) 0.14(0.54) K-968 A Pb 54.74 0.35(0.64) 0.19(0.35) 0.10(0.18) 0.42(0.76) Pb 54.74 0.24(0.44) 0.18(0.33) 0.11(0.18) 0.32(0.58) Ge 25.93 0.20(0.54) 0.08(0.31) 0.04(0.15) 0.17(0.66) B Pb 54.74 0.35(0.64) 0.21(0.39) 0.21(0.39) 0.46(0.85) Pb 54.74 0.25(0.46) 0.29(0.53) 0.21(0.39) 0.44(0.80) Ge 25.93 0.14(0.54) 0.09(0.35) 0.07(0.27) 0.18(0.69)

a25 kV excitation potential and five specimens of each glass

bCertified concentrations.

cValues in parentheses are relative errors in percent.

15
Table 8. Homogeneity Evaluation of Glasses K-458, K-489, and K-963a

Standard Deviations in Weight Percent0 Glass Exp Element Wt. %b se sr ss sp K-458 A Si 23.05 0.04(0.17) 0.07(0.30) 0.05(0.22) 0.10(0.43) Zn 3.01 0.03(1.00) 0.02(0.66) 0.01(0.33) 0.04(1.33) Ba 41.79 0.25(0.59) 0.16(0.38) 0.0

r\ OA/A nA\ 0.30(0.70) B Si 23.05 0.04(0.17) 0.07(0.30) 0.03(0.13) 0.09(0.39) Zn 3.01 0.03(1.00) 0.01(0.33) 0.0 0.03(1.00) Ba 41.79 0.26(0.62) r\ r\c\ / r\ *\ 1 \ 0.09(0.21) 0.07(0.17) 0.29(0.68) V A QQ rv-4oy ol roo [ZZ.Z5\ on fl C\A (C\ \Q.\ U.IW^U. loj u.uo^u.z /

;

n (\a (c\ i sa u.uo^u.oo; Zn 2.93 0.03(1.02) 0.02(0.68) 0.01(0.34) 0.04(1.37) Ba 39.53 0.24(0.61) 0.10(0.25) 0.0 0.26(0.66) D Si [22.23] 0.04(0.18) 0.06(0.27) 0.03(0.13) 0.15(0.67) Zn 2.93 0.03(1.02) 0.02(0.68) 0.02(0.68) 0.04(1.37) Ba 39.53 0.25(0.63) 0.19(0.48) 0.18(0.46) 0.36(0.91) K-963 A Si [21.96] 0.04(0.18) 0.03(0.14) 0.05(0.23) 0.07(0.32) Zn 2.95 0.03(1.02) 0.02(0.68) 0.0 0.04(1.36) Ba 39.21 0.25(0.64) 0.13(0.33) 0.0 0.27(0.69) B Si [21.96] 0.04(0.18) 0.06(0.27) 0.01(0.02) 0.07(0.32) Zn 2.95 0.03(1.02) 0.01(0.34) 0.02(0.68) 0.04(1.36) Ba 39.21 0.25(0.64) 0.0 0.01(0.03) 0.25(0.64)

a 15 kV excitation potential and five specimens of each glass. bCertified concentrations; numbers in brackets are not certified and are provided for Information Only.

cValues in parentheses are relative errors in percent.

16
Table 9. Homogeneity Evaluation of Glasses K-495, K-490, and K-546a

Standard Deviations in Weight Percent0 Glass Exp Element Wt. %b se SB ss Sp K-495 A Al

Al

10.89

10.89

0.10(0.92)

0.11(1.01)

0.0

0.03(0.28) 0.04(0.37)

0.06(0.55)

0.11(1.01) 0.13(1.19) B Al

Al

10.89

10.89

0.10(0.92)

0.11(1.01)

0.05(0.46) 0.00.07(0.64)

0.09(0.83) 0.13(1.19)0.14(1.29) C Al

Al

10.89

10.89

0.10(0.92) 0.11(1.01)

0.05(0.46) 0.04(0.37) 0.04(0.37)

0.11(1.01)

0.13(1.19)

0.16(1.47) K-490 A Al

Al

[10.15] no i si 0.10(0.98)

KJ. 1 1 ^ 1 .KJO ) 0.0KJ .KJ\i*\KJ . A,KJ ) 0.0 0KJ .KJ0

0.10(0.98) ovj. 1i 1i n^ i .wo o%\

B Al

Al

[10.15]

[10.15] 0.10(0.98)

0.11(1.08)

0.02(0.20)

0.04(0.39) 0.00.07(0.69)

0.10(0.98) 0.14(1.38) K-546 A AlAl

[10.06]

[10.06] 0.10(0.99)

0.11(1.09)

0.01(0.10)

0.0 0.02(0.20)

0.03(0.30)

0.10(0.99)

0.11(1.09) B Al

Al

[10.06]

[10.06] 0.10(0.99)

0.11(1.09)

0.05(0.50)

0.07(0.70) 0.12(1.19)0.15(1.49)

0.16(1.59)

0.19(1.89) D Al

Al

[10.06]

[10.06] 0.10(0.99) 0.10(0.99)

0.04(0.40) 0.04(0.40)

0.0 0.03(0.30)

0.11(1.09)

0.11(1.09)

a 15 kV excitation potential and five specimens of each glass.

bCertified concentrations; numbers in brackets are not certified and are provided for Information Only.

cValues in parentheses are relative errors in percent.

17
Table 10. Homogeneity Evaluation of Glasses K-496, K-497, and K-10133

Standard Deviations in Weight Percent0 Glass Exp Element Wt. %b Se Sfi Ss Sp K-496 A Mg 6.65 0.03(0.45) 0.04(0.60) 0.01(0.15) 0.05(0.75) P 32.98 0.12(0.36) 0.22(0.67) 0.10(0.30) 0.27(0.82) Al 6.47 0.03(0.46) 0.08(1.24) 0.04(0.62) 0.09(1.39) B Mg 6.65 0.03(0.45) 0.03(0.45) 0.0 0.04(0.60) P 32.98 0.12(0.36) 0.08(0.24) 0.10(0.30) 0.17(0.52) Al 6.47 0.03(0.46) 0.02(0.31) 0.01(0.15) 0.03(0.46) C Mg 6.65 0.04(0.60) 0.01(0.15) 0.01(0.15) 0.04(0.60) P 32.98 0.24(0.73) 0.25(0.76) 0.0 0.34(1.03) Al 6.47 0.03(0.46) 0.0 0.03(0.46) 0.04(0.62) K-497 A Mg 6.49 0.03(0.46) 0.05(0.77) 0.01(0.15) 0.05(0.77) P 31.59 0.12(0.38) 0.24(0.76) 0.12(0.38) 0.30(0.95) Al 5.97 0.03(0.50) 0.09(1.51) 0.04(0.67) 0.11(1.84) B Mg 6.49 0.03(0.46) 0.04(0.62) 0.02(0.31) 0.05(0.77) P 31.59 0.12(0.38) 0.12(0.38) 0.22(0.70) 0.27(0.85) Al 5.97 0.03(0.50) 0.05(0.84) 0.01(0.17) 0.06(1.01) C Mg 6.49 0.04(0.62) 0.01(0.15) 0.01(0.15) 0.04(0.62) p 1.59 0.21(0.66) 0.17(0.54) 0.0 0.27(0.85) Al J.y 1 \) .\) ) n nun 1 1\ U.U4^U.O / ) K-1013 A Mg 5.86 0.02(0.34) 0.05(0.85) 0.08(1.37) 0.10(1.71) P 32.26 0.13(0.40) 0.15(0.46) 0.05(0.15) 0.21(0.65) Al 6.08 0.03(0.49) 0.02(0.33) 0.03(0.49) 0.05(0.82) B Mg 5.86 0.02(0.34) 0.07(1.19) 0.07(1.19) 0.10(1.71) P 32.26 0.12(0.37) 0.30(0.93) 0.07(0.22) 0.19(0.59) Al 6.08 0.03(0.49) 0.03(0.49) 0.04(0.66) 0.05(0.82) F Mg 5.86 0.03(0.51) 0.05(0.85) 0.10(1.71) 0.11(1.88) P 32.26 0.22(0.68) 0.17(0.53) 0.04(0.12) 0.28(0.87) Al 6.08 0.03(0.49) 0.05(0.82) 0.04(0.66) 0.07(1.15)

a 15 kV excitation potential and five specimens of each glass. bCertified concentrations.

cValues in parentheses are relative errors in percent.

1 8
Table 1 1. Quantitative Analysis Of The Lead-Silicate Glasses, SRM 1781

Concentrations in Weight Percent

Glass Element Nominal Wet Chem. EPMA ICP Certified Value* K-456 Si 13.45 13.28 13.48 12.89 13.37 ± 10.24

13.29 13.58 13.54

13.32 13.64 Pb 66.12 65.71 65.18 65.67±10.26

65.77 65.85

65.77 65.74 K-493 Si 13.04 12.99 12.96 (13.09 ± 10.24) 13.01 13.28

13.01 13.29 Pb 64.13 63.37 62.84 63.28 ± 10.26 63.20 63.46

63.27 63.56 K-523 Si 12.90 12.81 13.13 (12.94 ± 10.24) 12.83 13.06

12.77 13.05 Pb 63.32 63.27 62.32 63.10 ± 10.26 63.30 63.38

63.17 63.18 *Numbers in parentheses are not certified and are provided for Information Only.
Table 12. Quantitative Analysis of the Lead-Germanate Glasses, SRM 1782

Concentrations in Weight Percent Glass Element Nominal Wet Chem. EPMA Certified Value* K-453 Ge 28.65 28.64

28.55 28.60

28.35

28.37

28.05

28.43 ± 10.34

Pb 54.51 54.20

54.10

54.15

54.38 54.40

54.03

54.21 ± 10.26

K-491 Ge 26.36 26.14

26.23 26.44

26.32

25.91 25.55

26.10 ± 10.34

Pb 55.10 54.82

55.01 54.74

54.58

54.53

54.45

54.69 ± 10.26

K-968 Ge 26.27 25.97

26.27 26.06

25.94 25.86

25.48

25.93 ± 10.34

Pb 54.91 54.89

54.85 54.92

54.78 54.66

54.36

54.74 ± 10.26
Table 13. Quantitative Analysis of Barium-Zinc-Silicate Glasses, SRM 1873

Concentrations in Weight Percent Glass Element Nominal Wet Chem. EPMA ICP DCP Certified Value* K-458 Si 23.08 22.65 23.42 23.12 22.98 23.05 ± 10.34 22.71 23.64 22.74 23.02

22.68 23.64

Neutron Activation

41.79 ± 10.20

K-489 Si 21.86 22.08 22.32 (22.23 ± 10.34)

2.93 ± 10.06

Zn 3.07 3.04 2.89 3.10

3.05 2.92 2.99

3.04 3.02 3.00

3.02 3.04

3.03 2.99

2.95 Ba 41.92 41.85 42.00

At n 1 41.71 A 1 A 1 41.41

41.95 41.82

Si 21.50 oo no 22.05 oo io LL.5L oo c\q oo ah 22.04 22.38 Zn o oo O OA O C3

O Q7 O Q/1 O OA Z.VO O QO Z.5 / o on

O Q1 z.y i O QO

2.88

rsa QO 1A

J7.ZO 1QJ7.7J

Si 21.99 21.93 21.24

21.97 22.27 21.93 22.43 Zn 3.00 3.00 2.95 3.00 2.96

2.99 2.84

2.94

2.90

2.91 2.89 Ba 39.52 39.59 39.32 39.40 38.58 39.36 38.99

3.01 ± 10.06

39.53 ± 10.20

K-963 Si 21.99 21.93 21.24 21.96 ±10.34)

2.95 ± 10.06

39.21 ± 10.48

*Numbers in parentheses are not certified and are provided for Information Only.

21
Table 14. Quantitative Analysis of the Lithium-Aluminum-Borate Glasses, SRM 1874

Concentrations in Weight Percent

Glass Element Nominal Wet Chem. EPMA Certified Value* K-495 Li 2.32 2.31 (2.33) 2.35 2.32

2.35 Al 0.58 10.91 11.13 10.89 ±0.23

10.88 10.87 10.88 10.85

10.67

10.75 B 23.29 22.99 (22.97) 22.99

22.93 K-490 li 2.17 2.20 (2.22) 2.22

2.22

2.22

Al 9.89 9.75 (10.15) 10.30

10.14

10.24 B 21.74 21.49 (21.48) 21.47

21.47 K-546 Li 2.16 2.16 (2.16) 2.14

2.17

Al 9.86 9.91 (10.06) 10.18 10.18 9.97

10.11 B 1.68 21.58 (21.62) 21.64

21.64 *Numbers in parentheses are not certified and are provided for Information Only.

22
Table 15. Quantitative Analysis of the Aluminum-Magnesium Phosphate Glasses, SRM 1875

Concentrations in Weight Percent Glass Element Nominal Wet Chem. EPMA Neut. Act. Certified Value K-496 Al 6.05 6.48

6.57

6.48

6.44

6.45

6.41

6.33 6.47 ± 0.20 6.33 6.36

6.43

6.33 Mg 5.44 6.73

6.71 6.73

6.56

6.61 6.52

6.65 ±0.17

P 34.71 32.74 33.58 32.98 ± 0.55 32.77

32.78 33.0733.11 K-497 Al

Mg

5.78

5.21

33.81

6.56

6.58

6.59 31.59

31.61 31.57

6.03

6.04

6.01

6.40

6.42

6.38 31.90

31.51 31.53

5.85 5.94

5.95

5.94

5.84

5.97 ± 0.22

6.49 ±0.17

31.59 ±0.58

K-1013 A

Mg

5.82

5.24

33.40

5.80

5.80

5.79 32.40

32.52

32.46

6.26

6.29

6.19

5.93 5.94

5.91 32.17

32.05

31.95

5.95 5.82

5.83 5.84

6.01

6.08 ± 0.21

5.86 ±0.26

32.26 ±0.56

23
Table 16. Voltages and Standards Used in Wavelength Dispersive Analysis

Element/Line Voltage (kV) Standard(s) MgKa 15 MgO

1 n10 K-412 glass-SRM 470

1 c

i J AI2U3

10 K-412 glass-SRM 470 SiKa 15 K-227*,Si02 PKa 10 Apatite

TiKa 10,15 Ti CrKa 15 Cr FeKa 15 Fe NiKa 20 Ni ZnKa 20 Zn GeKa 20 Ge

ZrLa 10,15 Zr BaLa 15 Benitoite CeLa 15 K-521 EuLa 15 Eu(P03 ) 3 * TaMa 15 Ta PbMaa 15 K-227*,PbTe

ThMa 10 ThF4 UMa 10 U

*These glasses were fabricated at NIST by the Inorganic Materials Division, Center for Materials Science and Engineering. Eu(POs)3 is a stoichiometric compound. The composition and wet chemistry values used for K-227 are

listed in table 17. The nominal values were used for glass K-521; these are 68 wt. percent B2O3, 25 wt. percent CeC>2 and 7 wt. percent LiC>2.

24
Table 17. Quantitative Analysis of Standard Glass K-227

Concentrations in Weight Percent Element Nominal Wet Chem. EPMA (standards)

Silicon 9.34 9.58 9.54 (Benitoite) Lead 74.26 73.86 73.31 (PbS)

Oxygen* 16.40 16.64 16.58

Total 100.00 100.08 99.45

*Calculated from stoichiometry

25
Table 18. Wet Chemistry Procedures Used in the Quantitative Analyses of SRM's 1871-1875 SRM 1871, Lead-Silicate Glasses

SiC>2 - Gravimetric determination by single or double dehydration with any silica remaining in solution determined by DC plasma spectrometry. PbO - Separation by extraction with sodium diethyldithiocarbamate in chloroform

followed by precipitation as PbCr04. SRM 1872, Lead-Germanate Glasses GeC>2 - Fusion of 230 mg. samples with a mixture of Na2C>2 and NaOH. Germanium

distilled as GeCl4 followed by titration with standard KIO3. PbO - Samples were dissolved in HCL to remove germanium. For K-453 and K-491

the lead was first isolated as PbS04 and then dissolved in excess standard MgEDTA solution. The equivalent amount of released magnesium was titrated with

standard CDTA. On sample K-968, the lead was determined gravimetrically as PbCr04. SRM 1873, Barium-zinc-silicate Glasses SK>2 - Same as silica in SRM 1871 above. ZnO - Complexometric determination after ion exchange separation following removal

of barium. BaO - Gravimetric determination after HF, HCIO4 dissolution and ion exchange

separation to remove interferences. Barium still remaining in solution determined by DC plasma spectrometry. SRM 1874, Lithium-aluminum-borate Glasses U2O - Solution of sample with HF and H2SO4. Interfering elements removed by the addition of CaO. Li20 determined with atomic absorption spectrophotometry after the removal of excess CaO.

AI2O3 - CDTA titration following fusion of the sample with K2SO7. B2O3 - Titration with sodium hydroxide following fusion with potassium pyrosulfate and complexation of interfering elements with CDTA.

SRM 1875, Aluminum-magnesium-phosphate Glasses AI2O3 - After fusion of K-496 with and an equimolar mixture of Na2C03 and Na2B4fJ7 and separation from P2O5 with a cation exchanger, a CDTA titration with a zinc back titration was used. MgO - After fusion with and an equimolar mixture of Na2C03 and K2CO3 and removal

of interferences, MgO in K-496 was determined by EDTA titration and in K-497

and K- 10 13 by gravimetry as Mg2P207.

P2O5 - After the above-described fusion (MgO), dissolution with HC1, and removal of

interferences with a cation exchanger, P2O5 was determined gravimetrically as Mg2P207.

26
Counts/10 s

o g

.2 T3 IS

c TM a

2 3 xi m

5 o

Oh I o E C

±3 <U c a

O o

c/5 f—

I

X O, O C/5

.5 o c

.a So

'S E °

O 3 T3 C <-> C

3 oo J=

S £ o

g J8

•5 B

S

-

27
Counts/ 10 s

+-> P

oo o

\0 OO

t—

1

J-H OS

| 8

s g

l <U i—I c/2

c a Soex

=? a 51

c5 > a ^ -3 13 » *-> C ai O | g|

1 11

^6'U d

03oio

X D O

3 * 8

Q

.5 g

b0 < 6

3 O

LiH 03 Pi X o 28
Counts/10 s

Figure 3. Periodic integrator homogeneity traces of silicon, barium and zinc simultaneoulsy recorded from Glass K-489 (15 Kv, 7.5 x 10"8 A beam current). In the traces on the right, the specimen was advanced 1-u.m under a 1-um diameter electron beam after each 10-second counting

period. To the left is a time-resolved trace taken from repeated 10-second counting periods on a

stationary specimen with a 20 x 20 urn scanning raster. The double-headed arrows to the right represent a range of ±3a/N around the average number of counts per 10 seconds, N, for the entire

trace. 29
Counts/ 10 s

4*

Figure 4. Periodic integrator homogeneity traces of magnesium, phosphorous and aluminum

simultaneoulsy recorded from Glass K-497 (15 Kv, 7.5 x 108 A beam current). In the traces on

the right, the specimen was advanced 1-u.m under a 1-u.m diameter electron beam after each 10- second counting period. To the left is a time-resolved trace taken from repeated 10-second

counting periods on a stationary specimen with a 20 x 20 urn scanning raster. The double-headed

arrows to the right represent a range of ±3VN around the average number of counts per 10

seconds, N, for the entire trace. 30
K-456 - Quant. Determinations for Silicon

14.0 I

1 1 1

' K-456 - Quant. Determinations for Lead

66.5 . , , , ,

Nominal WetChem Probe ICP Nominal WetChem Probe

Quant. Determinations for Silicon

Nominal WetChem Probe

K-493 - Quant. Determinations for Lead

64.5

Nominal WetChem Probe

K-523 - Quant. Determinations for Silicon

13.3

- 13.1 s

§ 12.9

Nominal WetChem Probe

Quant. Determinations for Lead

Nominal WetChem Probe

Figure 5. SRM 1871. Distribution plots of the results of wet chemistry, electron microprobe, and

inductively coupled plasma spectrometry analyses compared to the nominal compositions.

31
Quant. Determinations for Germanium K-453 - Quant. Determinations for Lead

54.6

Nominal WetChem Probe Nominal WetChem Probe

Quant. Determinations for Germanium K-491

55.2 Quant. Determinations for Lead

Nominal WetChem Probe Nominal WetChem Probe

Quant. Determinations for Germanium Quant. Determinations for Lead

Nominal WetChem Probe Nominal WetChem Probe

Figure 6. SRM 1872. Distribution plots of the results of wet chemistry and electron microprobe

analyses compared to the nominal compositions.

32
Figure 7. SRM 1873. Distribution plots of the results of wet chemistry, electron microprobe,

inductively coupled and direct current plasma spectrometry analyses compared to the nominal

compositions.

33
Figure 8. SRM 1874. Distribution plots of the results of wet chemistry and electron microprobe

analyses compared to the nominal compositions.

34
0> o o o o Si 0 ° ° ° ° r: o o o o o o ^ <° <° <° <° '«><dioioifi V <b <o to as » iri

Figure 9. SRM 1875. Distribution plots of the results of wet chemistry, electron microprobe, and

neutron activation analyses compared to the nominal compositions.

35
REFERENCES

1. Marinenko, R. B., Heinrich, K. F. J., and Ruegg, F. C, Micro-homogeneity

Studies of NBS Standard Reference Materials, NBS Research Materials, and Other

Related Samples, NBS Spec. Pub. 260-65, Sept. 1979, 84 pp.

2. Marinenko, R. B., Biancaniello, F., DeRobertis, L., Boyer, P. A., and Ruff, A. W., NBS Spec. Pub. 260-70, May 1981, 25 p. 3. Paule, R. C. and Mandel, J., Concensus Values and Weighting Factors, J. Res. of

Natl. Bur. Stands. (U.S.), 87, (5), p. 377(1982).

4. Yakowitz, H., Myklebust, R. L., and Heinrich, K. F. J., FRAME: An On-Line

Correction Procedure for Quantitative Electron Probe Microanalysis, NBS Tech. Note 796, Oct. 1973, 46 pp.

5. Henoc, J., Heinrich, K. F. J., and Myklebust, R. L., A Rigorous Correction Procedure for Quantitative Electron Probe Microanalysis (COR), NBS Tech. Note

769, Aug. 1973, 127 pp.

6. Riley, J. E., Mitchell, J. W., Downing, R. G., Fleming, R. F., Lindstrom, R. M., and Vincent, D. H., Materials analysis using Thermal Neutron Reactions: Applications, Materials Science Forum, 2, 1984, pp 123-132.

7. Downing, R. G., Fleming, R. F., Langland, J. K., and Vincent, D. H., Neutron Depth Profiling at the National Bureau of Standards, Nuclear Instruments and Methods in Physics Research, 218, 1983, pp. 47-51.

8. Newbury, D. E. and Myklebust, R. L., Monte Carlo Electron Trajectory Simulation of Beam Spreading in Thin Foil Targets, Ultramicroscopy, 3, 1979, pp. 391-395.

36
ADDENDUM

The glasses were analyzed by R. L. Korotev, Senior Research Scientist, at Washington University, St. Louis, Missouri, using neutron activation analysis. The

results of his analyses for several of the elements present in these glasses are listed in the

table below. Trace amounts of other elements were also observed, but are not reported

here. The complete report of these analyses can be obtained from R. Marinenko at NIST

(Bldg.222 Rm. A113, Gaithersburg, MD. 20899). Neutron Activation Analysis of Glasses for Microanalysis

(Washington University in St. Louis)

Concentration in weight percent GLASS

K-458 K-493 K-491 K-489 K-490* K-497

Ele. Fe 0.25±0.10 <0.34 <0.77 <0.32 Zn 3.00±.04 3.56±0.07

Zr 0.37+0.08 0.24±0.06 0.47±0.10 0.19±0.07 0.43±0.12 Ba 40.1±0.60 3.7911.1 Ce 0.344±0.006 0.259±0.005 0.663±0.012 0.326±.005 0.602+0.011 Ta 0.78±0.04 0.63±0.03 1.13±0.05 0.71±0.03 0.89±0.04 GLASS

K-523 K-968 K-963 K-546* K-1013

Ele. Cr 0.184±0.006 0.154±0.005 0.296±0.009 0.0508±0.0017 0.219±0.007 Zn 2.92±0.06 Ba 0.61±0.15 0.33+0.11 36.40±1.80 0.50±0.09 0.68±0.25 Eu 0.563±0.016 0.444±0.012 0.82±0.02 0.347±0.007 0.652±0.018 Th 0.078±0.003 0.062 1±0.002 0.125±0.004 0.077±0.0017 0.097±0.003 U 0.103±0.003 0.082±0.003 0.175±0.007 0.153±0.003 0.134±0.004

Uncertainties are one standard deviation estimates of analytical precision (counting statistics). Single samples were analyzed and specimen sizes were 12-36 mg.

* Because of flux loss resulting from the high boron concentrations in these samples, the listed values are low by a factor of up to 2-3; this has been confirmed3 by neutron self-shielding calculations15 which predicted a flux loss of 50 percent.

aR. F. Fleming and R. M. Lindstrom, private communication

bR. F. Fleming, Neutron Self-shielding Factors for Simple Geometries, Int. J. Appl. Radiat.

Isot. Vol. 33, pp 1263-8, 1982.

37
al coUB-.fi.i ldn

Jiectttar>| Rational ^itraw of ^tandardfi

(Herttfttate of (Attaints

Standard Reference Material 1871

Lead-Silicate Glasses for Microanalysis

K-456, K-493, and K-523

This Standard Reference Material (SRM) is intended primarily for the analysis of glasses, ceramics, and minerals by

microanalytical techniques. It consists of three different lead-silicate glasses in rod-form approximately 2 x 2 x 20 mm,

which can be divided into several specimens for microanalysis. These glasses were specifically fabricated for use in microanalytical techniques such as electron probe microanalysis (EPMA) and secondary ion mass spectrometry (SIMS). The major constituents of these glasses show no heterogeneity of any practical significance on the micrometer scale. Lead is certified in all three glasses, while silicon is certified in glass K-456 only. For the dopant elements, the values in parentheses are electron microprobe analyses and the values in brackets are nominal values calculated from the weighed amounts of the oxides added to the melts. The oxygen values were calculated from the stoichiometry of the oxides. The

values in parentheses and brackets are provided as information only and are not certified.

Table 1. Compositions in Weight Percent Element Glass K-456 K-493 K-523 Pb 65.67 ± 0.26 63.28 ±0.26 63. 10 ±0.26

Si 13.37 ± .24 (13.09 ± .24) (12.94 ± .24) O (20.35) (20.58) (20.80) Mg (0.12) [0.10] Al (0.13) [0.11] P (.24) [.25] Ti (.20) [.19] (.21) [.19] Cr (.20) [.21] Fe (.25) [.22] Ni (.25) r.241 Ge ( 20) [.29] Zr (.38) [.36] (.33) [.36] Ba (.61) [.55] Ce (.53) r.55] Eu (.73) [.60] Ta (-64) [,72]» Th (.08) [.10] U (.23) [.11] Total (99.38) (99.08) (100.19) 'Neutron activation: Ta = (0.74)

Washington, DC 20234 May 1, 1984 Stanley D. Rasberry, Chief

Office of Standard Reference Materials

38
Lead and silicon values were determined by wet chemical analysis and EPMA. In addition, inductively coupled plasma

spectrometry was used to determine silicon in glass K.-456. The certified values and the nominal values for silicon were

determined from the weighted average of the two or three different methods of analysis. A standard deviation of the

certified value was calculated from the variances within as well as between the different analytical procedures. A pooled

standard deviation was then obtained for each element by combining the standard deviations from all three glasses. The

error cited is two times the pooled standard deviation of the certified value. The dopant elements, present as oxides in concentrations of 2 percent or less in glasses K-493 and K-523, were

determined with the electron microprobe, and are compared to the nominal values in brackets. These dopant elements

are not certified for either composition or homogeneity. Tantalum in glass K-493 was also determined by neutron

activation analysis. The glasses were tested for microhomogeneity using periodic integrator traces and random sampling techniques. Inters specimen homogeneity was also tested. No inhomogeneity of any practical significance was observed. The glasses were prepared by D.H. Blackburn and D.A. Kauffman, NBS Center for Materials Research.

Quantitative wet chemical analyses were performed by J.B. Bodkin under the direction of N. H. Suhr, Pennsylvania State

University, University Park, Pa. The inductively coupled plasma spectrometry was performed by R.L. Watters, NBS Center for Analytical Chemistry.

Quantitative EPMA and homogeneity testing were performed by R.B. Marinenko, NBS Center for Analytical Chemistry. Data reduction for the quantitative analysis, was done with the NBS correction procedure, COR.

Neutron activation analysis was done by G.J. Lutz, NBS Center for Analytical Chemistry. The technical measurements leading to certification were coordinated by R.B. Marinenko under the direction of H. Rook, NBS Center for Analytical Chemistry.

Statistical consultation was provided by R.C. Paule, NBS National Measurement Laboratory. The support aspects involved in the certification and development of this Standard Reference Material was coordinated through the Office of Standard Reference Materials by R.W. Seward.

'Paule, R.C. and Mandel, J., J. Res. of Nat. Bur. Stds., 87, No. 5, p. 377 (1982).

2 Henoc, J., Heinrich, K.F.J., and Myklebust, R.L., Nat. Bur. Stds. Technical Note 769, (1973).

39
U. S. Department of Commerce

Malcolm Baldrigc Secretary

National Bur«u of Standards Ern«t Ambler. Director Rational ^nvtnn of jittattdartta

(Eerttfttate of (Analysts

Standard Reference Material 1872

Lead-Germanate Glasses for Microanalysis

K-453, K-491, and K-968

This Standard Reference Material (SRM) is intended primarily for the analysis of glasses, ceramics, and minerals by microanalytical techniques. It consists of three different Jead-germanate glasses in rod-form approximately

2 x 2 x 20 mm, which can be divided into several specimens for microanalysis. These glasses were specifically fabricated

for use in microanalytical techniques such as electron probe microanalysis (EPMA) and secondary ion mass spectro- metry (SIMS). The major constituents of these glasses show no heterogeneity of any practical significance on the micrometer scale. Lead and germanium are certified in all three glasses. For the dopant elements, the values in parentheses are electron microprobe analyses and the values in brackets are nominal values calculated from the weighed amounts of the oxides added to the melts. The oxygen values were calculated from the stoichiometry of the oxides. The values in parentheses and brackets are provided as information only and are not certified.

Table 1. Compositions in Weight Percent Element Glass K-453 K-491 K-968 Ge 28.43 ± 0.34 26.10±0.34 25.93 ± 0.34 Pb 54.21 ± .26 54.69 ± .26 54.74 ± .26 O (16.73) (16.45) (16.67) Mg (0.22) [0.08] Al (0.10) [0.09]

Si (.11) [.09] P (.21) [.20] Ti (.14) [.16] (.16) [.16] Cr (.19) [.17] Fe (17) [-18] Ni (.20) [.19] Zr (.26) [.30] (.48) [.30] Ba (.46) [.45] Ce (.59) [.46] Eu (.64) [.49] Ta (.52) [.59]* Th (.12) [.08] U (.05) [.09] Total (99.37) (99.13) (100.07) •Neutron activation: Ta = (0.58)

Washington, DC 20234 Stanley D. Rasberry, Chief May 1, 1984 Office of Standard Reference Materials

40
Lead and germanium values were determined by wet chemical analysis and EPMA. The certified values were determined from the weighted average of the two different methods of analysis. A standard deviation of the certified value was

calculated from the variances within as well as between the different analytical procedures. A pooled standard deviation was then obtained for each element by combining the standard deviation from all three glasses. The error cited is two

times the pooled standard deviation of the certified value. The dopant elements, present as oxides in concentrations of 2 percent or less in glasses K-491 and K-968, were

determined with the electron microprobe, and are compared to the nominal values in brackets. These dopant elements

are not certified for either composition or homogeneity. Tantalum in glass K-491 was also determined by neutron

activation analysis. The glasses were tested for microhomogeneity using periodic integrator traces and random sampling techniques. Inter- specimen homogeneity was also tested. No inhomogeneity of any practical significance was observed. The glasses were prepared by D.H. Blackburn and D.A. Kauffman, NBS Center for Materials Research.

Quantitative wet chemical analyses were performed by J.B. Bodkin and B. Takano under the direction of N.H. Suhr, Pennsylvania State University, University Park, Pa. Quantitative EPMA and homogeneity testing were performed by R.B. Marinenko, NBS Center for Analytical Chemistry. Data reduction for the quantitative analysis, was done with the NBS correction procedure, COR.

Neutron activation analysis was done by G.J. Lutz, NBS Center for Analytical Chemistry. The technical measurements leading to certification were coordinated by R.B. Marinenko under the direction of

H. Rook, NBS Center for Analytical Chemistry.

Statistical consultation was provided by R.C. Paule, NBS National Measurement Laboratory. The support aspects involved in the certification and development of this Standard Reference Material was coordinated through the Office of Standard Reference Materials by R.W. Seward.

1 Paule, R.C. and Mandel, J., J. Res. of Nat. Bur. Stds., 87, No. 5, p. 377 (1982).

2 Henoc, J., Heinrich, K.F.J., and Myklebust, R.L., Nat. Bur. Stds. Technical Note 769, (1973).

41
Emcsl l^mblfr. ftrcclor Rational ^areau of j^lantlartte

(Eerttfttate of (Analyst*

Standard Reference Material 1873

Barium-Zinc-Silicate Glasses for Microanalysis

K-458, K-489, and K-963

This Standard Reference Material (SRM) is intended primarily for the analysis of glasses, ceramics, and minerals by

micro-analytical techniques. It consists of three different barium-zinc-silicate glasses in rod-form approximately

2 x 2 x 20 mm, which can be divided into several specimens for microanalysis. These glasses were specifically fabricated

for use in microanalytical techniques such as electron probe microanalysis (EPMA) and secondary ion mass spectro- metry (SIMS). The major constituents of these glasses show no heterogeneity of any practical significance on the micrometer scale. Barium and zinc are certified in all three glasses, while silicon is certified in glass K-458 only. For the dopant elements,

the values in parentheses are electron microprobe analyses and the values in brackets are nominal values calculated from

the weighed amounts of the oxides added to the melts. The oxygen values were calculated from the stoichiometry of the

oxides. The values in parentheses and brackets are provided as information only and are not certified.

Table 1. Compositions in Weight Percent Element Glass K-458 K-489 K-963 BaZn

41.79 ± 0.20

3.01 ± .06 39.53 ± 0.20 193 ± .06 39.21 ± 0.482.95 ± .06 SiO

Mg

Al

23.05 ± .34

(31.86) (22.23 ± .34) (31.70)

(0.11) [0.15]

(21.96 ± .34) (32.00)

(0.34) [0.14] P

TiCr

Fe

(.27) [.28]

(.35) [.32]

(.33) [.36]

(.32) [.36]

(.31) [-30] NiGe

ZrCe

(.40) [.52] [-80]

(.33) [.34]

(.47) [.42]

(.61) [.53] EuTa

PbThU

(.95) [1.03]*

(1.32) [1.19]

(.95) [.88]

(.06) [.13] (16) [.17] Total (99.71) (100.59) (100.00) •Neutron activation: Ta = (1.03)

Washington, DC 20234 May 1, 1984 Stanley D. Rasberry, Chief

Office of Standard Reference Materials
Barium, zinc, and silicon values were determined by wet chemical analysis and EPMA. In addition, plasma emission spectrometry (inductively coupled and direct current plasma spectrometry) were used to determine silicon in glass K-458. The certified values and the silicon information values were determined from the weighted average of the two or three

different methods of analysis. A standard deviation of the certified value was calculated from the variances within as well as between the different analytical procedures. For zinc and silicon, a pooled standard deviation was then obtained

for each element by combining the standard deviations from all three glasses. For barium, a pooled error was determined from glasses K-458 and K-489, as the error for K-963 was quite different from the other two glasses. The error cited in the

table is two times the pooled (or individual) standard deviation of the certified value. The dopant elements, present as oxides in concentrations of 2 percent or less in glasses K-489 and K-963, were

determined with the electron microprobe, and are compared to the nominal values in brackets. These dopant elements

are not certified for either composition or homogeneity. Tantalum in glass K-489 was also determined by neutron acti- vation analysis. The glasses were tested for microhomogeneity using periodic integrator traces and random sampling techniques. Inter- specimen homogeneity was also tested. No inhomogeneity of any practical significance was observed. The glasses were prepared by D.H. Blackburn and D.A. Kauffman, NBS Center for Materials Research.

Quantitative wet chemical analyses were performed by J.B. Bodkin and B. Takano under the direction of N.H. Suhr, Pennsylvania State University, University Park, Pa. The inductively coupled and direct plasma spectrometry was performed by R.L. Watters and M.S. Epstein, respectively, NBS Center for Analytical Chemistry.

Quantitative EPMA and homogeneity testing were performed by R.B. Marinenko, NBS Center for Analytical Chemistry. Data reduction for the quantitative analysis, was done with the NBS correction procedure, COR.

Neutron activation analysis was done by G.J. Lutz, NBS Center for Analytical Chemistry. The technical measurements leading to certification were coordinated by R.B. Marinenko under the direction of H. Rook, NBS Center for Analytical Chemistry.

Statistical consultation was provided by R.C. Paule, NBS National Measurement Laboratory. The support aspects involved in the certification and development of this Standard Reference Material was coordinated through the Office of Standard Reference Materials by R. W. Seward.

'Paule, R.C. and Mandel, J., J. Res. of Nat. Bur. Stds., 87, No. 5, p. 377 (1982).

2 Henoc, J., Heinrich, K.F.J., and Myklebust, R.L., Nat Bur. Stds. Technical Note 769, (1973).

43
U. S. Department of Commerce

Malcolm Baldrigc Secretary" Rational ^mmn of j^tandartta

(Eerttfttate of (Analysts

Standard Reference Material 1874

Lithium-Aluminum-Borate Glasses for Microanalysis

K-495, K-490, and K-546

This Standard Reference Material (SRM) was fabricated primarily for use in the analysis of glasses, ceramics, and

minerals by microanalytical techniques such as electron probe microanalysis (EPMA) and secondary ion mass spectro- metry (SIMS). SRM 1874 consists of three different lithium-aluminum-borate glasses in rod-form, approximately

2 x 2 x 20 mm, which can be divided into several specimens for microanalysis. The aluminum concentration in glass K-495 is the only value certified for SRM 1874. For lithium and boron, information values from wet chemistry analysis are in parentheses, and for aluminum in glasses K-490 and K-546, information

values obtained by EPMA are in parentheses. No error limits are given for information values because they were

obtained by only one method. The homogeneity for aluminum was examined by EPMA. No serious inhomogeneities were observed. For the dopant elements, the values in parentheses were obtained by microprobe analysis and the values

in brackets are nominal values calculated from the weighed amounts of oxides added to the melts. The oxygen values were calculated from the stoichiometry of the oxides. The values in parentheses and brackets are provided for information only and are not certified.

Table I. Compositions in Weight Percent

Element Glass K-495 K-490 K-546

Li (2.3) (2.2) (12) Al 10.8910.23 (10.2) (10.1) B (23.0) (21.5) (21.6) O (63.49) (60.74) (61.36) Mg (0.17) [0.17] P (0.42) [0.43] Ti (0.31) [0.35] (0.39) [0.34] Cr (0.14) [0.14] Fe (0.38) [0.38] Ni (0.39) [0.41] Ge (0.50) [0.51] Zr (0.53) [0.63] (0.52) [0.64] Ba (0.99) [0.96] Ce (1.46) [0.97] Eu (1.21) [1.06] Ta (1.02) [1.25] Th (0.16) [0.16] U (0.24) [0.20] Pb (1.47) [1.44]

Si (0.19) [0.20] Total (99.68) (100.01) (100-39)

Gaithcrsburg, MD 20899 December 28, 1984 Stanley D. Rasberry, Chief

Office of Standard Reference Materials

44
Aluminum in K-495 and lithium and boron in all three glasses were determined by wet chemistry. EPMA was used to determine aluminum in all glasses. The certified value for aluminum in K-495 was determined based on the weighted

average of the two different methods of analysis.

1 The quantitative error, ±2s, is two times the pooled standard deviation of the certified value for aluminum determined in three glasses of a related SRM (SRM 1875) plus glass K-495 in SRM 1874. One standard deviation of the certified value was calculated from the variances within, as well as between,

the different analytical procedures. The dopant elements, present as oxide constituents of 2 percent or less in glasses K-490 and K-546, were determined

with the electron microprobe, and are compared to the nominal values in brackets. These dopant elements arc not

certified either for composition or for homogeneity. Aluminum in all three glasses was tested for microhomogeneity using periodic integrator traces and random sampling

techniques. Interspecimen homogeneity was also tested. A small inhomogeneity error for a single measurement was

determined from the within and between specimen errors. This inhomogeneity error is included with the quantitative error in the uncertainty (two standard deviations) for the certified composition. The variability between the different analytical methods (the quantitative error) is the predominant contribution to the uncertainty. The glasses were prepared by D.H. Blackburn and D.A. Kauffman, NBS Center for Materials Research.

Quantitative wet chemical analyses were performed by J.B. Bodkin under the direction of N.H. Suhr, Pennsylvania

State University, University Park, Pa. Quantitative EPMA and homogeneity testing were performed by R.B. Marinenko, NBS Center for Analytical Chemistry. Data reduction for the quantitative analysis was done with the NBS correction procedure, COR.

Neutron Activation analysis was done by R.M. Lindstrom and G.J. Lutz, NBS Center for Analytical Chemistry. The technical measurements leading to certification were coordinated by R.B. Marinenko under the direction of H.L. Rook, NBS Center for Analytical Chemistry.

Statistical consultation was provided by R.C. Paule, NBS National Measurement Laboratory. The support aspects involved in the certification and development of this Standard Reference Material were coordinated through the Office of Standard Reference Materials by R. W. Seward.

'Paule, R.C. and Mandel. J., J. Res. of Nat. Bur. Stds., 87. No. 5, p. 377 (1982).

2 Henoc, J. Heinrich, K.F.J., and Myklebust, R.L., Nat. Bur. Stds. Tech. Note 769, 1973.

45
U. S. Department of Commerce

Malcolm Baldrigc Secretary ^National ^ureau of Jitartdards

(Eeriifttate of JVnalgsts

Standard Reference Material 1875

Aluminum-Magnesium-Phosphate Glasses for Microanalysis

K-496, K-497, and K-1013

This Standard Reference Material (SRM) was fabricated primarily for use in the analysis of glasses, ceramics, and

minerals by microanalytical techniques such as electron probe microanalysis (EPMA) and secondary ion mass

spectrometry (SIMS). SRM 1875 consists of three different aluminum-magnesium-phosphate glasses in rod-form, approximately 2 x 2 x 20 mm, which can be divided into several specimens for microanalysis. Aluminum, magnesium, and phosphorus are certified in all three glasses. These major constituents show no serious heterogeneity on the micrometer scale. For the dopant elements, the values in parentheses are from electron probe

microanalyses and the values in brackets are nominal values calculated from the weighed amounts of oxides added to the

melts. The oxygen values were calculated by difference because the stoichiometry of the phosphorus oxides in the glasses

is unpredictable. The values in parentheses and brackets are provided for information only and are not certified.

Table 1. Compositions in Weight Percent

Element Glass K-496 K-497 K-1013

Al 6.4710.20 5.97 ± 0.22 6.08 ± 0.21 Mg 6.65 ±0.17 6.49 ±0.17 5.86 ± 0.26 P 3198 ±0.55 31.59 ±0.58 32.26 ± 0.56 O (53.90)* (52.46)* (53.05)* Pb (0.86) [0.92]

Si (0.13) [0.13] B [0.05] Ti (0.22) [0.21] (0.21) [0.22] Cr (0.14) [0.23] Fe (0.26) [0.24] Li [0.0005] Ni (0.31) [0.26] Ge (0.34) [0.33] Zr (0.32) [0.40] (0.45) [0.41] Ba (0.52) [0.61] Ce (0.94) [0.62] Eu (0.53) [0.67] Ta (0.71) [0.88]** Th (0.10) [0.11] U (0.15) [0.13] Total (100.00) (100.00) (100.00)

* Oxygen values were calculated by difference. *• Neutron activation: Ta = (0.83).

Gaithersburg, MD 20899 Stanley D. Rasberry, Chief December 28, 1984 Office of Standard Reference Materials

46
Aluminum was determined in all three glasses by EPMA and neutron activation, and in K-496 by wet chemical analysis. Phosphorus and magnesium were determined in all three glasses by EPMA and wet chemical analysis. The certified values were calculated as the weighted average of the two or three different methods of analysis. The quantitative error, ±2s, for each clement is two times the pooled standard deviation of the certified value for all three glasses. One standard

deviation of the certified value was calculated from the variances within, as well as between, the different analytical procedures. The dopant elements, present as oxides in compositions of 2 percent or less in glasses K-497 and K- 10 1 3, were determined

with the electron microprobe, and are compared to the nominal values in brackets. These dopant elements are not

certified either for composition or for homogeneity. Tantalum in glass K-497 was determined by neutron activation

analysis. The glasses were tested for microhomogeneity using periodic integrator traces and random sampling techniques. Inter- specimen homogeneity was also tested. A small inhomogeneity error for a single measurement was obtained from these

tests. This error is included (with the quantitative error) in the uncertainty (two standard deviations) for each of the

certified compositions. For phosphorus, the inhomogeneity error is the major contribution to the uncertainty; while for aluminum and magnesium, the variability between the different analytical methods (the quantitative error) is the predominant contribution to the uncertainty. The glasses were prepared by D.H. Blackburn and D.A. Kauffman, NBS Center for Materials Research.

Quantitative wet chemical analyses were performed by J.B. Bodkin under the direction of N.H. Suhr, Pennsylvania

State University, University Park, Pa. Quantitative EPMA and homogeneity testing were performed by R.B. Marinenko, NBS Center for Analytical Chemistry. Data reduction for the quantitative analysis was done with the NBS correction procedure, COR."

Neutron Activation analysis was done by R.M. Lindstrom and G.J. Lutz, NBS Center for Analytical Chemistry. The technical measurements leading to certification were coordinated by R.B. Marinenko under the direction of

H.L. Rook, NBS Center for Analytical Chemistry.

Statistical consultation was provided by R.C. Paulc, NBS National Measurement Laboratory. The support aspects involved in the certification and development of this Standard Reference Material were coordinated through the Office of Standard Reference Materials by R.W. Seward.

'Paulc, R.C. and Mandel, J., J. Res. of Nat. Bur. Stds., 87, No. 5, p. 377 (1982)

2 Henoc, J. Heinrich, K.F.J., and Myklebust, R.L., Nat. Bur. Stds. Tech. Note 769, 1973.

47
NBS

Standard

Reference

Materials

U.S. DEPARTMENT OF COMMERCE

^ National Bureau of Standards

Standard Reference Materials 1871-1875

Glasses for Microchemical Analysis

Fall 1984

The NBS Office of Standard Reference Materials announces a new series of Standard Reference Materials (SRM's) for use in microanalytical techniques such as electron-probe microanalysis and secondary-ion mass spectrometry. These SRM's, 1871-1875, are glasses that show no serious inhomogeneities on the micrometer scale for the certified constituents. The individual glasses are in rod form, approximately 2 x 2 x 20 mm. Each SRM represents a different

glass matrix, and in each SRM there is a base-composition glass plus two glasses of the same base composition to which

several dopant elements have been added. The different matrices and dopants make these glasses useful in the analysis of complex unknowns. The compositions of the fifteen glasses in this SRM series are listed in the attached table. The values for the currently

certified elements are not enclosed in either parentheses or brackets. Those enclosed in parentheses are informational

values.while those in brackets are nominal values calculated from the weighed material added to the glass melt during

preparation. These SRM's may be purchased for $196.00 per set from:

Office of Standard Reference Materials Room B311 Chemistry Building National Bureau of Standards

Gaithersburg, MD 20899

Telephone: (301) 921-2045

1084

48
SRM

1875

Glass

K-496

K-497

K-1013

(Wt.

%)

(0.86) (0.13)

(0.34) (0.52)

32.98

31.59

32.26

6.65

6.49

5.86

6.47

5.97

6.08

[0.05] (0.32)

(0.45)

(0.22)

(0.21)

(0.94)

-

ro.7n

.......

(0.26)

[0.0005]

(0.31) (0.53)

—

(0.15)

(0.14)

(53.90)*

(52.46)*

(53.05)* (0000 1)

(00

001)

(0000 1)

SRM

1874 ? hi

Is

$§\ i

: :

: :

: : : : MM

(0.42) (0.17)

10.89

(10.2)

(10.1)

(23.0)

(21.5)

(21.6)

(0.53)

(0.52)

(0.31)

(0.39)

(1.46)

C1.021

|S fill

is N: : : : iff i i i

i ill,

(0.14)

(63.49)

(60.75)

(61.36)

(99.68)

(100.01)

(100.39)

1

—

-J

SRM

1873

Glass

K-458

K-489

K-963

(Wt.

%)

-

(1.32)

-•

23.05

(22.23)

(21.96)

(0-39)

41.79

39.53

39.21

3.01

2.93

2.95

(0.33)

-

—

(0.34)

(0.11)

IIIN

inn

iiii

iiii

(0.35)

[0.0009]

--

(0.33)

(0.95)

(0.16)

rn

nfii

-

(0.31)

(31.86)

(31.84)

(31.96)

(99.71)

(100.79)

(99.88)

SRM

1872

Glass

K-453

K-491

K-968

(Wt.

%)

54.21

54.69

54.74

(o.ii)

28.43

26.10

25.93

(0.46)

(0.21)

---

(0.22)

(0.10)

if Si i

: s s : :

11 111

I.i ill

: i i : i

i | Hll

Ann

ii Nil

(0.19)

(16.73)

(16.45)

(16.67)

(99.37)

(99.16)

(100.07)

SRM

1871

|

Glass

K-456

K-493

K-523

(Wt.

%)

65.67

63.28

63.10

13.37

(13.09)

(12.94)

(0.24)

(0.61)

(0.24)

(0.12)

(0.13) [0.04] (0.38)

(0.33)

(0.20)

(0.21)

(0.53)

-

-

(0.25)

[0.0005]

(0.25) (0.73)

-

(0.23)

(0.08) (0.20)

(20.35)

(20.58)

(20.82)

(99.39)

(99.12)

(100.10)

I £tfO«N 0.2<fflN P<3(2£3 o

Total

49

4. TITLE AND SUBTITLE Standard Reference Materials: Glasses for Microanalysis: SRM's 1871-1875

5. AUTHOR(S) R. B. Marinenko, D. H. Blackburn, and J. B. Bodkin

6. PERFORMING ORGANIZATION (IF JOINT OR OTHER THAN NIST, SEE INSTRUCTIONS)

U.S. DEPARTMENT OF COMMERCE

NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY

GAITHERSBURG, MD 20899

7. CONTRACT/GRANT NUMBER

8. TYPE OF REPORT AND PERIOD COVERED Final

NIST-114A U.S. DEPARTMENT OF COMMERCE

(REV. 3-89) NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY

BIBLIOGRAPHIC DATA SHEET

1. PUBLICATION OR REPORT NUMBER NIST/SP-260/112

2. PERFORMING ORGANIZATION REPORT NUMBER

3. PUBLICATION DATE February 1990

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (STREET, CITY, STATE, ZIP)

Same as No. 6

10. SUPPLEMENTARY NOTES

] DOCUMENT DESCRIBES A COMPUTER PROGRAM; SF-185, FIPS SOFTWARE SUMMARY, IS ATTACHED.

11. ABSTRACT (A 200-WORD OR LESS FACTUAL SUMMARY OF MOST SIGNIFICANT INFORMATION. IF DOCUMENT INCLUDES A SIGNIFICANT BIBUOGRAPHY OR

LITERATURE SURVEY, MENTION IT HERE) The preparation, homogeneity tests, and the quantitative analyses of the Glasses

for Microanalysis, SRM's 1871-1875, are described. Each Standard Reference Material

(SRM) represents a different glass matrix; these are lead-silicate (SRM 1871), lead- germanate (SRM 1872), barium-zinc-silicate (SRM 1873), 1 ithium-aluminum-borate

(SRM 1874), and aluminum-magnesium-phosphate (SRM 1875). There are three glasses in each SRM, one composed only of the matrix oxides and the other two having small additions (less than two percent) of several other elements in oxide form.

12. KEY WORDS (6 TO 12 ENTRIES; ALPHABETICAL ORDER; CAPITAUZE ONLY PROPER NAMES; AND SEPARATE KEY WORDS BY SEMICOLONS) electron probe microanalysis (EPMA) ; glasses for microanalysis; microhomogeneity

quantitative EPMA; wavelength dispersive analysis (WDA)

13. AVAILABILITY UNLIMITED FOR OFFICIAL DISTRIBUTION. DO NOT RELEASE TO NATIONAL TECHNICAL INFORMATION SERVICE (NTIS). ORDER FROM SUPERINTENDENT OF DOCUMENTS, U.S. GOVERNMENT PRINTING OFFICE, WASHINGTON, DC 20402. ORDER FROM NATIONAL TECHNICAL INFORMATION SERVICE (NTIS). SPRINGFIELD, VA 22161.

14. NUMBER OF PRINTED PAGES 60

15. PRICE

ELECTRONIC FORM



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