bluuebunny/crossref_metadata_2025 huggingface dataset:
Applications of Dual-Energy X-ray Computed Tomography to Structural Ceramics*
Authors: Ellingson W. A. , Vannier M. W.
Published: March 2019

Advanced structural ceramics (Si3N4, SiC, A12O3, ZrO2) are rapidly being developed with sufficient fracture toughness to be considered for engineering applications such as internal combustion engine components, rotating turbine engine components, and heat recovery systems. X-ray computed tomography (CT) is a promising nondestructive evaluation method for these ceramics, but beam hardening presents a serious problem in the interpretation of CT images generated with polychromatic X-ray sources by creating artifacts . Dual-energy X-ray techniques have the potential to eliminate these problems. In addition, in theory, dual energy allows generation of quasimonochromatic equivalent images, which should allow verification of theoretically determined optimum energies. In using dual-energy methods, the high-and low-energy images are nonlinearly transformed to generate two energy-independent images characterizing the integrated Compton/photoelectric attenuation components. Characteristic linear combinations of these two "basis" images can serve to identify unknown materials and generate synthesized monoenergetic images.

The dual-energy method has been used to study structural ceramics as well as liquids that are close to ceramic materials in atomic number and mass density. The work was done on a Siemens DR-H CT machine with 85- and 125-kVp energy levels. Test samples included Si3N4 cylinders ranging from 10 to 50 mm in diameter, liquid Freon TF, and densified SiC.
XRF in Japan and China
Authors: Arai Tamoya
Published: March 2019

This report will describe scientific activity in XRF as well as some practical application topics for Japan and China.
Low Level Iodine Detection by TXRF in a Reactor Safety Simulation Experiment
Authors: Hegedüs F. , Winkler P. , Wobrauschek P. , Streli Christina
Published: March 2019

In the event of an accident in a light water moderated nuclear plant, the fission products escape from the water moderator in form of gas bubbles. One of the most important fission products is Iodine. Presently there are only rough estimations of the escape of Iodine. The aim of the experiment planned at the Swiss Federal Institute for Reactor Research (EIR) is to simulate the conditions of an accident and to measure the amount of Iodine which escapes from the moderator water into the space inside the reactor containment.

It is supposed that at 5 m depth in a water pool, the canning of the fuel element explodes releasing 1-3 liter large gas bubbles containing the volatile fission products. The Iodine vapor concentration, saturated in the gas bubble, will be about 3 mg/l. It is expected that the water strongly absorbs the Iodine vapor and the I concentration in the gas bubble arriving at the water surface will be strongly reduced to a few ug/l.
Background Intensities and Their Utilization in Quantitative Analysis by Monochromatically Excited Energy-Dispersive X-Ray Fluorescence
Authors: Rachetti Alessandra , Wegscheider Wolfhard
Published: March 2019

In monochromatically excited energy-dispersive X-ray fluorescence spectrometry, the spectral background has mainly been investigated for a better understanding of its origin and nature, or with the aim to reduce its magnitude for an improvement of detection limits.

The observation that the background intensity can largely be ascribed to a residual polychromatic fraction of the exciting radiation has led to the derivation of an empirical relationship between the scattering characteristics of a sample and the observed background intensity. This dependence constitutes the basis of a matrix correction procedure useful for samples with a considerable fraction of light elements.

Two algorithmic variations are presented: one that relies on the definition of a single matrix element, and a second one that can be used in conjunction with the measurement of the incoherently scattered exciting radiation. These options are useful if direct quantification of either or both scatter peaks is not feasible.

Results are presented for a variety of Standard Reference Materials.
Comparison of Dilution Strategies for Dealing with Unanalyzed Elements in X-Ray Fluorescence Analysis
Authors: DeGroot Peter B.
Published: March 2019

One method of dealing with unanalyzed light elements in x-ray fluorescence analyses is to add a relatively large quantity of a diluent to the sample. The interelement effects on the measured radiation are then essentially all due to the diluent, and the effects of the unanalyzed elements are ignored. The general practice has been to use a diluent compound composed of light elements. The rationale for this is that light elements absorb the analyte radiation less strongly than heavy ones, leaving higher net intensity available after dilution. However, since absorption effects are greater with heavy elements, a smaller dilution factor can be used to reach the analyte concentration at which the effects of unanalyzed elements on the analyte radiation are negligible compared to diluent effects. In many cases, the smaller dilution factor almost exactly compensates for the increased absorption. There is essentially no intensity penalty for using a heavy element diluent. In fact, there are some advantages to doing so. The lower dilution factor with heavy elements can avoid problems with multiple dilutions or accurate weighing and homogeneous blending of very small quantities necessary to achieve high dilution factors. Significantly less continuum radiation is scattered from heavy element matrices, and signal-to-background ratio can be higher in some parts of the spectrum. With high energy analyte lines, heavy element dilution results in infinitely thick samples, simplifying sample preparation. Theoretical intensity calculations using the XRFll matrix correction program are used to predict the appropriate dilution factor for a range of analyte x-ray emission wavelengths with a variety of diluents. The results are verified experimentally.
Measurements of Soft and Ultrasoft X-Rays with Total Reflection Monochromator
Authors: Arai Tomoya
Published: March 2019

The development of X-ray spectrographic analysis of light elements, which are O, C and B, has bee n performed for many applications using an end-window type X-ray tube with Rh-target and thin Be-window, wavelength dispersing devices, which are synthetic multilayers or total reflection mirror (with a specific filter) and a gas flow proportional counter with a thin film window. In Fig. 1 factors related to the intensity measurements in X-ray fluorescence analysis are shown. The excitation efficiency in the soft and ultrasoft X-ray region is very low because of the lower intensity of primary X-rays and low fluorescence yield of light elements. Instead of the wavelength dispersive method of Bragg reflection, having high resolution and low reflectivity, monochromatization combining total reflection by a selected mirror and an appropriate filter offered an alternate approach in order to increase measured intensity with reasonable optical resolution. Synthetic multilayers which have higher resolution and lower intensity compared with the performance of the mirror method have become popular for the detection of soft and ultrasoft X-ray region.
Comparison of Dual-Channel Wavelength and Secondary-Target Energy-Dispersive X-Ray Spectrometers
Authors: Croke John F. , Nicolosi Joseph A.
Published: March 2019

Over the past 30 years, X-ray fluorescence spectrometry has become one of the more valuable methods for the qualitative and quantitative analysis of materials. Today, there are many methods of instrumental analysis available, and among the factors that will be taken into account in the method of selection are:

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Accuracy

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Range of application

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Speed

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Sensitivity

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Reliability

No one technique can provide all of the features that a given analyst requires. XRF does offer good overall performance over the widest range of elements. Speed, accuracy, and versatility are among the features that have made XRF the method of choice for over 15,000 laboratories worldwide.
The Efficiency of the Recessed Source; Geometry for EDXRF Analysis of Metal Impurities in Oils
Authors: dos Santos J.M.F. , Conde C. A. N. , Ferreira L. F. Requicha , De Campos A. J.
Published: March 2019

The efficiency of the recessed source geometry for the analysis of the content of wear metals in engine lubricant oils by Energy Dispersive X-Ray Fluorescence (EDXRF) methods is calculated by a Monte Carlo simulation considering X-ray detectors of the Gas Proportional Scintillation Counter type and excitation by Cd-109, Cm-244 and Fe-55 radioactive sources. Calculated spectra for the case of a typical aircraft oil with Cu, Fe, Cr, Ti, Sn and Ag impurities in the p.p.m. range were obtained and results are presented that allow the prediction of the counting rate per mCi and p.p.m. of the impurity content. The performance of the system is discussed concerning its potential applications to in-line monitoring of the wear metals.
Wide Area Networking of XRF Generated Geochemical Data in a National Geological Survey
Authors: Smith T. K.
Published: March 2019

A previous paper by this author (1984) described the evolution of XRF analysis in the British Geological Survey. More recent developments are described here, with particular reference to wide-area networking. Since the Survey was founded in 1835 it has been to a large extent concerned with the amassing of data. In most cases the information is permanently retained, in contrast to some other applications where the data are stored only temporarily. The result of this permanent storage is that a very large database has been created and continues to grow at an increasing rate, partly as the result of extension of the terms of reference to include the continental shelf. Another reason is that geochemical, geophysical and geotechnical information is now included, and automated methods of measurement and data capture now exist.
X-Ray Fluorescence Determination of Trace Elements in Complicated Matrices
Authors: Yawen Liu , Qinmin Fan , Daolun Li
Published: March 2019

A method for the direct determination of trace elements in light element matrices is described. The intensity of Compton scatter of the incident X-rays from the specimen was used to evaluate the apparent absorption factor for the direct correction for matrix effects. This permits the use of single element standards for samples of varied and complicated matrix composition. Relative errors of approximately 5% were obtained for results in the concentration range of 10-200 ppm.
Rapid Non-Destructive X-Ray Characterization of Solid Fuels/Propellants
Authors: Ananthanarayanan T. S. , Mayo W. E. , Rosemeier R. G. , Miller R. S.
Published: March 2019

Numerous studies have been conducted into the microstructural origin of the instability and unpredictability of various energetic materials. Some of these materials are RDX/HMX, Ammonium Perchlorate, Aluminum, etc. Many techniques both destructive and non-destructive have so far been utilized in an attempt to quatify the energetic properties of their composites. These composites may contain one or more energetic constituents in an elastomeric binder. Non-destructive X-ray characterization techniques have been successfully employed to measure several microstructural parameters. Previous studies have shown considerable differences among various production grade RDX. These studies reveal marked differences in the amounts of residual elastic strain and the distribution of dislocations (residual plastic strain) in the constituent RDX phase.

The focus of this study is to develop a technique for quantitative constituent phase analysis of solid-propellant (fuel) composites using conventional diffractometry. The use of a Curved Position Sensitive Detector (CPSD) greatly enhances the technique and allows real time applications in production environments. Through the use of computer based Systems and "user friendly" software the required Operator, skill and training have been considerably reduced. The CPSD System has been successfully used to quantify constituent phases (peak heights) and the amounts of residual elastic strain (peak shifts) in these molecular crystal powder mixtures.

It is envisioned that rapid, automated, non-destructive X-ray characterization techniques will greatly facilitate production based propellant quality control. A thorough understanding of the relationship between the energetics and microstructural parameters can also he obtained.
Computing X-Ray Powder Diffraction Intensities and Bragg Angles Using a Microcomputer
Authors: Sujjayakorn P. , Stadelmaier H. H. , Russ J. C.
Published: March 2019

Programs exist to compute X-ray diffraction patterns (angles and intensities) for specified atomic arrangements using mainframe computers. We report here a microcomputer version (in Basic, to n m on a standard Apple ][ computer with two disk drives and optionally a printer). Additionally, the program offers considerable flexibility in entering atomic positions and using symmetry relations to simplify the input for complex unit cells, and provides a visual display of the unit cell in any orientation.

There are a variety of search-match algorithms that compare measured powder diffraction patterns to previously determined standards, such as the JCPDS powder diffraction file. These have been implemented on computers ranging from mainframes to microcomputers, with tradeoffs in the practical size of the standards file and the speed of the search.
High Temperature X-Ray Diffraction Study of Sol-Gel Derived Pb(ZrxTi1-x)O3 Powders
Authors: Haun M.J. , Lee Y.H. , McKinstry H.A. , Cross L.E.
Published: March 2019

The lattice parameters of sol-gel derived Pb(ZrxTi1-x)O3 powders were determined as a function of temperature using a microcomputer automated Picker x-ray diffractometer. The spontaneous strain was calculated from the lattice parameters, and used with other experimental data to develop a thermodynamic phenomenological theory for the PZT solid solution system. A second tricritical point, where the transition changes front first to second order, was found to occur near or possibly at the morphotropic phase boundary between the tetragonal and high temperature rhombohedral phases. Using an equation derived from the theory, the spontaneous tilt angle of the oxygen octahedra in the low temperature rhombohedral phase was calculated from the experimental spontaneous strain data.
Relationship Between Thermal Expansion and Crystal Chemical Parameters in Diborides
Authors: McKinstry H.A. , Chai Lai Daik , Sara R.V. , Spear K.E.
Published: March 2019

Thermal expansion is an interesting, ubiquitous and neglected property of materials. Recently, Lenain et al. (1985) and Limaye (1986) have been investigating anisotropy in the low-expansion structures of the sodium zirconium phosphate family. In the hexagonal structure one axis expands while another contracts. In going from the calcium to the strontium analog the anisotropy actually changes sign. A change in anisotropy between CrB2 and TiB2 had been observed by R.V. Sara (1960). The results in Fig. 1 obtained by high temperature x-ray diffraction measurements indicate that for TiB2 the thermal expansion of the c-axis is greater than the expansion of the a-axis, whereas for CrB2 the reverse is true.
Experimental Methods for Determination of Precision and Estimation of Accuracy in XRD Residual Stress Measurement
Authors: Ruud C.O. , Snoha D.J. , Ivkovich D.P.
Published: March 2019

It is important to establish precision and accuracy of an X-ray diffraction (XRD) residual stress measurement procedure in order to compare capabilities of instrumentation and techniques, as well as to provide confidence limits for experimental data. There is no broadly acceptable method for establishment of precision and accuracy. This paper describes a proposed approach and one which is used at The Pennsylvania State University.

One impediment to the measurement of precision and accuracy is that no standard specimen with a known residual stress level is available. Proposed standard specimens have been abandoned for various reasons, including the concern for stability of the original stress condition and the existence of stress gradients, i.e., stress inhomogeneity, in the specimens. However, there is one type of specimen which has been accepted by ASTM as an alignment and zero residual stress confirmation standard. That type of specimen is a powdered sample of metal or ceramic which provides XRD peaks in the vicinity of the Bragg angle in which residual stress measurements are to be performed.

Some researchers tend to report detector counting statistics as the uncertainty of stress measurement but such statistical scatter accounts for only one part of uncertainty in precision and accuracy. The total uncertainty is best determined directly through repeated residual stress measurements performed by removal and readdressing the test specimen or through a repetition of measurements under predictably changing conditions.

This paper describes results from the use of powder specimens to establish the repeatability of measurements with a portable instrument after removal and readdressing of the specimens. Also, results showing the uncertainty of the measured stress change in specimens subjected to known loads are discussed.
High Resolution Digital X-Ray Rocking Curve Topography
Authors: Ananthanarayanan T.S. , Mayo W.E. , Rosemeier R.G.
Published: March 2019

This study presents a unique and novel enhancement of the double crystal diffractometer which allows topographic mapping of X-ray diffraction rocking curve half widths at about 100-150μm spatial resolution. This technique can be very effectively utilized to map micro-lattice strain fields in crystalline materials. The current focus will be on the application of a recently developed digital implementation for the rapid characterization of defect structure and distribution in various semiconductor materials.

Digital Automated Rocking Curve (DARC) topography has been successfully applied for characterizing defect structure in materials such as: GaAs, Si, AlGaAs, HgMnTe, HgCdTe, CdTe, Al, Inconnel, Steels, BaF2 PbS, PbSe, etc. The non-intrusive (non- contact & non-destructive) nature of the DARC technique allows its use in studing several phenomena such as corrosion fatigue, recrystallization, grain growth, etc., in situ. DARC topography has been used for isolating regions of non-uniform dislocation density on various materials. It is envisioned that this highly sophisticated, yet simple to operate, system will improve semiconductor-device yield significantly.

The high strain sensitivity of the technique results from combination of the highly monochromated and collimated X-ray probe beani, the State of the art linear position-sensitive detector (LPSD) and the high-precision specimen goniometer.
Secondary Ion Mass Spectrcmetry and Related Techniques
Authors: Asher Sally
Published: March 2019

Secondary ion mass spectrometry (SIMS) Is a well established technique for the microcharacterization of solid samples. SIMS is able to detect all the elements in the periodic table, from H to U, and their isotopes. It Is unique among the common surface analytical techniques in its ability to detect H directly. SIMS has high sensitivity, ppm to ppb, for most elements. It has good depth and lateral resolution, 5-10nm and 1-2µ, respectively. Sample preparation is minimal and almost any sample oan be accommodated. In addition, molecular SIMS offers the chance to obtain chemical information about the sample. As a result of these features, SIMS has found applications in many fields; The techniques related to SIMS that will be described at the end of this paper differ primarily in their methods of generating secondary ions. This leads to differences in the information obtained and the types of samples which can be analyzed. This paper will be a brief introduction to the field of SIMS. Several reviews and a recently published text are available in the literature.
Automated X Ray Topography and Rocking Curve Analysis: A Readability Study
Authors: Fatemi M.
Published: March 2019

There is considerable interest in the microelectronics industry to obtain high-resolution images, as well as precise measures of defect densities in “ device quality” thin films and substrates. In the field of x-ray diffraction, research groups worldwide are intensely pursuing the relevant applications of computerized x-ray rocking curve analysis and topography. Production-type, on-site rocking curve instrumentation has already been introduced into the market, and potential uses of x-ray topography are also under consideration.

In the present study, the merits and limitations of these two techniques are critically evaluated. Possible pitfalls of automated data collection are pointed out and conditions under which meaningful measurements may be made are explored. It is shown that reliable results may nearly always be obtained with reasonable care when each method is applied subject to its own mode of operation. However, extreme caution is needed when digitized data initially collected for topography is subsequently used for rocking curve analysis; otherwise, the correspondence between the interpretation and actual defect configuration may be vitiated. Thus, additional tests will be necessary to ensure the validity of the results.
Dynamic Theory of Asymetric X-Ray Diffraction for Strained Crystal Wafers
Authors: Berreman D. W. , Macrander A. T.
Published: March 2019

A very accurate 8X8 matrix approach to dynamical theory of X-ray diffraction in which fewer approximations are made than in the classic vonLaue approach, is described here. The method is related to the very general matrix method of Kokushima and Yamakito, and is particularly suited to numerical solution with a computer. It can be used to solve problems in ideal, undistorted crystals with high precision even at near grazing incidence without special consideration of refraction or external reflection. It is also easy to apply to problems where periodicity of oblique Bragg planes varies in the direction normal to the surface. Such strain may be induced, for example, by variation of composition with depth. Certain problems wherein simultaneous diffraction by two sets of Bragg planes occurs can also be treated by this approach.
Residual Stress in Two Dental Alloys During Porcelain Application
Authors: Bagby M. , Marshall SJ , Marshall GW
Published: March 2019

Residual stresses in dental castings are widely held to be the cause of distortion and change of fit in ceramic bonded to metal dental restorations. Residual stresses are thought to result from the casting process and from ceramic/metal mismatch of thermal expansion coefficients. Such stresses have not been confirmed experimentally. The purpose of this study was to measure residual stress with x-ray diffraction at the various porcelain application steps for two noble dental alloys with two dental opaque porcelains.
X-Ray Line Broadening Study on Shock-Modified Hematite
Authors: Zhang Y. , Stewart J. M. , Morosin B. , Graham R. A. , Hubbard C. R.
Published: March 2019

Hematite (α-Fe2O3) powder compacts have been subjected to controlled, quantitative high pressure shock loading at peak pressures from 8-27 GPa and preserved for post shook analysis. The broadened x-ray diffraction peak profiles have been analyzed to determine the residual lattice strain and the coherent crystallite sizes. Maximum modification effects are observed near 17 GPa with strain values near 3 x 10-3 and size values near 200 Å suggesting annealing at higher shock pressure, resulting from the higher shock temperature.
The Estimation of Limits of Detection in RIM Quantitative X-Ray Diffraction Analysis
Authors: Davis Briant L.
Published: March 2019

In earlier papers, the reference intensity method (RIM) of quantitative x-ray diffraction was described in terms of the theoretical basis (Davis, 1980), error propagation (Davis, 1981), filter sample preparation technology for eliminating preferred orientation (Davis and Johnson, 1982; Davis, 1986), and special applications to amorphous-bearing samples using mass absorption measurements (Davis and Johnson, 1987). This paper describes application of counting statistics to the determination of the lower limit of detection (LLD) of components quantitatively measured by the RIM procedure. With this discussion, virtually all phases of the RIM methodology will have been described.
Automated Quantitative Multiphase Analysis Using a Focusing Transmission Diffractometer in Conjunction With a Curved Position Sensitive Detector
Authors: Foster B. A. , Wolfel E. R.
Published: March 2019

The method for quantitative X-ray diffraction analysis of multiphase mixtures presented here is based on transmission measurements of thin samples. The integral of all reflections of interest are measured with a position sensitive detector at one time while the transmission factor of the sample is measured simultaneously with a scintillation counter. The method has the advantages that only a few (1-5) mg of substance are required, absorption effects due to sample matrix are measured directly and the method is automated. The measurements are made with the STOE/ Nicolet Automatic Focusing X-ray Diffraction system in conjunction with the STOE/Nicolet Curved Position Sensitive Detector.
High Temperature Stability of Superconducting YBa2 Cu30x as Characterized by X-Ray Diffraction
Authors: Eatough M. O. , Aselage T. L. , Keefer K. D. , Ginley D. S. , Morosin B.
Published: March 2019

The recent discovery of superconducting oxide ceramics with critical temperatures (Tc) near 100°K has stimulated research at an unprecedented pace. Single phase YBa2 Cu30x (x = 6.9), the subject of most of the interest, is an oxygen deficient 1:1:3 stacked perovskite derivative, (The structure of this materials has been described by a number of authors, many of whom are referenced by Jorgensen et al.) At room temperture it has an orthorhombic structure with lattice parameters near: a = 3.82Å, b = 3.88Å, and c - 11.68 Å. At lower oxygen values (x≤6.5) the structure is tetragonal with lattice parameters near: a = 3.86 and c = 11.80. It has been suggested that tetragonal YBa2 Cu30x is not superconducting. YBa2 Cu30x, regardless of oxygen content, is referred to here as 123.
Asymmetric Crystals Re-Visited
Authors: Short Michael A. , Robie Stephen E.
Published: March 2019

An asymmetrically cut single crystal is, generally, a large flat X-ray monochromating crystal whose principal surface has been cut an angle to the diffracting planes being utilised.

The use of such a crystal was suggested by Stephen and Barnes in 1935 as a means of obtaining a narrow intense beam of monochromatic X-rays. Fankuchen was first to demonstrate this effect experimentally. A number of symmetrically cut mosaic single crystals, including lithium fluoride, was studied by Evans, Hirsch and Kellar and by Gay, Hirsch and Kellar in the beam condensing (beam narrowing) mode only.
Laser Aligned Laue Technique for Small Crystals
Authors: Green Robert W. , Marsh Donald M.
Published: March 2019

An X-ray/Laser technique is described for producing Laue patterns on very small (1mm2) crystal surfaces where it is otherwise not possible to mechanically align the surface of the crystal perpendicular to an X-ray beam. This technique has been used to determine the orientation of the diamond inserts in cutting tool bits.
Using Digitised X-Ray Powder Diffraction Scans as Input for a New Pc-At Search/Match Program
Authors: Caussin P. , Nusinovici J. , Beard D.W.
Published: March 2019

A Search/Matcti program lias 'beea written for the IBM PC AT computer that is capable of -using "background - subtracted, digitized 2-ray powder diffraction scans as inputs in addition to the d/I data traditionally used. This novel procedure has proved especially effective when numerous unresolved lines are present in the pattern. The method is also less demanding of data quality thaii the peak location programs. The program may he extended to searching & data "base of digitized standard patterns.

The program, has several parameters that can- "be adjusted, including chemistry. The results from the Johnson/Vand list type of output are directly accessible to the interactive graphics program. This gives the diffraction!st a fast method for verifying the phase identification. Because of the speed of fixed point computation techniques, the 52,791 pattern file can be scanned in about 90 seconds.

This paper will illustrate the utility of the program.
Window Area Effects in the Detector Efficiency for Source Excited EDXRF Geometries
Authors: dos Santos J.M.F. , Costa Benilde E.O.
Published: March 2019

The efficiency dependence on detector window area for three different geometries of source excited energy dispersive X-ray fluorescence (EDXRF) analysis systems are calculated using the Monte Carlo method. Two typical samples (coal and oil) are considered for discussion. The results show that the efficiency is affected mainly by geometric factors: source-to-sample distance and absorption of the exciting X-rays; fluorescent photon self-absorption has a much smaller effect.
Appearance Potential X-Ray Fluorescence Analysis
Authors: Kirkland J. P. , Gilfrich J. V. , Elam W. T.
Published: March 2019

Appearance potential spectroscopy has been practiced for many years. In essence, it simply involves ramping the energy of the exciting quanta across excitation edges and observing the onset of a signal. Because of the relative simplicity with which the energy can be controlled, electrons have been the conventional quanta employed. The signals which have "appeared", characteristic of the atoms being studied, have been either Auger electrons or x-ray. The literature is replete with references to appearance potential measurements; the applications have, for the most part, demonstrated interesting physics, but analytical measurements have not been numerous.
A Scanning X-Ray Fluorescence Microprobe with Synchrotron Radiation
Authors: Gohshj Y. , Aoki S. , Iida A. , Hayakawa S. , Yamaji H. , Sakurai K.
Published: March 2019

A scantling X-ray fluorescence(XRF) microprobe using WoIter type 1 optics was developed, and micro and trace element analysis was carried out using synchrotron radiation up to 10 keV as an excitation source. The design parameters of the optical system and the performance of the system, such as the beam size and the intensity, are described. The MDL obtained for Mn was 6 ppm in relative concentration and about 0.1 pg in absolute amount. The estimated spatial resolution was better than 10 um.
Intensity and Distribution of Background X-rays in Wavelength Dispersive Spectrometry
Authors: Arai Tomoya , Omote Kazuhiko
Published: March 2019

In the speetrographie analysis of composite elements by fluorescent x-rays, significant developments have been made in low atomic number element measurement and improvement of analytical performance in trace element measurements.

For the analysis of trace elements, background intensity governs analytical accuracies and the lowest detection limit in a sample.
The Early Years of X-Ray Diffraction and X-Ray Spectrometry
Authors: de Vries J. L.
Published: March 2019

Wilhelm Conrad Röntgen was born on 27-03-1845, 150 years ago, in Lennep- Remscheid in Westphalen, Germany, from a German father and a Dutch mother. He remained an only child. When he was 3 years old, the family moved to Apeldoom in the Netherlands. His parental home exists and will be the Röntgen bar. After going to school in Apeldoorn, he went to a technical school in Utrecht, where he finished in 1865. He enrolled in the University of Utrecht in the Netherlands, but found that he did not have the right certificates to pass the examinations. He then went to Zurich to the newly stifted Eidgenössische Technische Hochschule, where restrictions were less severe. In 18869, he got his doctorate on ‘Thermodynamics of gases.’ He was a brilliant student with a wide variety of interests.
Software Development for X-Ray Diffraction Analysis 1950-1995
Authors: Smith Deane K. , Gorter Syb
Published: March 2019

Software has come a long way from the days of plug board wiring and multi-step computations which were characteristic of the 1950s, In the early days, hardware development led software development partly because the evolution of the hardware was so rapid and partly because the software was primarily developed for specific units. In those days the major cost was in the hardware and the software development generally involved only salary for relatively few individuals. Modern computer costs are now within the reach of the individual, and the money that goes into programming and programs is now the major cost.

This paper reviews some of the steps in the evolution of software as it affected the analysis of powder diffraction data. Many “new” programs are adaptations of earlier routines to a different computer platform, but there are many truly new programs implementing inproved concepts for extracting crystal information from the digitized diffraction data.
Application of Tapered Monocapillary in a Laboratory Mxrf Set-Up
Authors: Gao N. , Ponomarev I. , Xiao Q. F. , Gibson W. M. , Carpenter D. A.
Published: March 2019

Simulation and experimental work that compare the performance of straight and tapered monocapillaries when used with laboratory x-ray sources are reported. Detailed simulations for various taper profiles give several important conclusions for optimizing the design of a tapered monocapillary. Several tapered monocapillaries were prepared. With a 16W x-ray source, beam intensities of 4×105 photon/sec/μm2 and 3×105photon/sec/μm2 of Cu Kα x rays were obtained from the tapered monocapillaries for output diameters of 8μm and 3.5μm, respectively. These intensities are 1.4 and 1.5 times that obtained from straight capillaries with the same output beam sizes at the experimental set-up optimized for a straight capillary. In addition to the gain in x-ray flux, the tapered monocapillaries produce output beams with significantly reduced high energy bremsstrahlung radiation and increased flux stability with respect to shifts of the x-ray source spot.
New Tools for Grazing Incidence Diffraction Measurements: Comparison of Different Primary and Secondary Beam Conditioners
Authors: Stabenow Rainer , Haase Alfried
Published: March 2019

Grazing incidence diffraction (GID) is a powerful tool for the structural characterization of thin films. Unlike traditional Bragg-Brentano geometry (divergent X-ray beam, focusing geometry), GID experiments are enhanced by a parallel beam of high intensity. Classical conditioning of the X-ray beam is done by using small slits on the primary beam side and a long Soller slit in combination with a flat crystal (e.g. graphite, lithium fluoride or germanium) or an energy dispersive detector on the secondary beam side. However, new alternatives for beam conditioners are becoming available which promise increased performance. X-ray beam optics using either planar or graded parabolically curved multilayer mirrors of high reflectivity have been constructed for the primary beam side as well as for the secondary beam side.
New Rotating Anode X-Ray Generator For XAFS Experiments
Authors: Sakurai Kenji
Published: March 2019

A high-power X-ray generator equipped with a lanthanum hexaboride cathode has been developed for X-ray absorption fine structure experiments. A high tube-current of more than 1,000 mA can be provided when operated at low tube-voltage of less than 20 kV. In addition, the focal width is narrow enough (less than 0.1 mm) to ensure good energy resolution. Extremely intense monochromatic X-rays (106 ∼ 107 counts/(sec.mm2) at the sample position), which are completely free from higher order harmonics and tungsten contamination lines, are available, when a Johansson-type spectrometer is employed. The filament life has been significantly prolonged by the high vacuum specification of the tube.
A Polycrystalline Thin Film Diffractometer for Asymmetric Diffraction Using Parallel Beam and High Resolution Parallel Slits
Authors: Toraya H. , Yoshino J.
Published: March 2019

A polycrystalline thin film diffractometer for asymmetric diffraction at a fixed incident angle using parallel beam and high-resolution-parallel slits has been developed. Well collimated CuK α1 incident beam was obtained by coupling of a rotating anode generator with a channel-cut crystal monochromator. The diffracted beam was analyzed with parallel slits with 0.17° angular aperture. The observed profiles of CeO2 standard powder sample were analyzed by using an individual profile fitting technique. The minimum full-width at half-maximum (FWHM) was 0.15° in the 20 range of 40° ∼ 70°, and the variation of FWHM with 20 was almost independent of the incident angle. Intensity in asymmetric diffraction was enhanced compared to that in the symmetric 0-20 scan, and its variation was well in accordance with the theory. The use of the parallel slits compromizes the intensity and resolution for polycrystalline thin film diffraction in the present setup, but gives the high quality of diffraction data for structural study.
Novel GIX2 Apparatus for Thin Film Analysis Using Color Laue Method
Authors: Horiuchi Toshihisa , Ishida Kenji , Hayashi Kouichi , Matsushige Kazumi , Shibata Atsushi
Published: March 2019

In modern technology, thin-layered materials with layer thickness in nanometer ranges have been utilized for various advanced components such as integrated circuits, magnetic heads and disks, X-ray mirrors and coated window glasses. For the analysis of such materials, powerful probes, fluorescence(TXRF)1), diffraction(TXRD) 2-4) and reflectivity(GIXR) 5-7), formed by X-rays in conjunction with total reflection phenomena can provide important information on element composition, crystalline structure, layer thickness, electron density and interfacial roughness.
Sample Curvature Effects on d-versus-sin2ѱ plots for Residual Stress Analysis
Authors: Ward Allan , Allison Heidi , Zimmerman Brian , Hendricks R. W.
Published: March 2019

This paper corrects assumptions made by previous authors regarding the magnitude of the error in d-versus-sin2ѱ plots resulting from deviations of the sample surface from the focusing circle. The results show that the effect is not significant for ordinary residual stress measurements. This investigation has also shown that shapes in d-versus- sin2ѱ plots, similar to the sample curvature effect, may exist in samples with large residual stresses. Interpretation of the data should consider the magnitude of the apparent stress, which allows one to distinguish between apparent sample curvature effects and other causes.
Neutron and X-Ray Scattering Studies of the Metallurgical Condition and Residual Stresses in Weldalite Welds
Authors: Spooner S. , Pardue E.B.S.
Published: March 2019

Neutron and x-ray scattering methods of residual stress measurement were applied to plasma arc welds made in aluminum-lithium alloy test panels as part of an evaluation of materials for use in welded structures. In the course of these studies discrepancies between x-ray and neutron results from the heat affected zone (HAZ) of the weld were found. Texture changes and recovery from the cold work, indicated in peak widths, were found in the HAZ as well. The consideration of x-ray and neutron results leads to the conclusion that there is a change in solute composition which modifies the d-spacings in the HAZ which affects the neutron diffraction determination of residual stresses. The composition changes give the appearance of significant compressive strains in the HAZ. This effect and sharp gradients in the texture give severe anomalies in the neutron measurement of residual stress. The use of combined x-ray and neutron techniques and the solution to the minimizing of the neutron diffraction anomalies are discussed.
An Analysis of Macro- and Microstresses Around a Fatigue Crack Tip
Authors: Almer J. D. , Cohen J. B. , Kirk W. D. , Winholtz R. A.
Published: March 2019

We have investigated the stresses existing before and during fatigue crack growth in a 1080 spheroidized steel. The total stress state, which consists of triaxial macro- and microstress components, has been measured around the fatigue crack tip using x-ray microbeam diffraction. A tapered glass capillary of 210μm diameter has been developed to provide increased intensity, smooth diffraction peaks and good spatial resolution. Findings indicate that stresses generated by the growing crack are mainly macro stresses, and dominate over pre-existing residual stresses around the tip.
Depth Profiling Biaxial Stresses in Sputter Deposited Molybdenum Films; Use of the Cos2φ Method
Authors: Ballard B. L. , Predecki P. K. , Watkins T. R. , Kozaczek K. J. , Braski D. N. , Hubbard C. R.
Published: March 2019

Depth profiles of intrinsic in-plane, biaxial stresses were obtained as a function of τ, the 1/e penetration depth, in a 1.0 um thick planar d. c. magentron sputter deposited molybdenum film using asymmetric grazing incidence x-ray diffraction (GIXD). τ was varied between 20 and 276 Å. The stresses σ11 and σ22 were characterized in the directions parallel and perpendicular to the long axis of the cathode respectively using a cos2φ method. The results show that starting from τ=17Å, σ11 and σ22 are compressive and become rapidly more compressive with a minimum at τ ∼ 20 - 40 Å thereafter increasing gradually toward tensile values. The reasons for the shape of the stress gradient are not well understood but may be related to the relaxation of the stresses at the tops of the columnar Zone T-type microstructure and to the oxygen gradient in the film.
Effect of Macro and Micro Stresses on Hardness of Titanium Aluminides
Authors: Tabata Hiroyuki , Yajima Zenjiro , Hirose Yukio
Published: March 2019

The changes in micro structure and hardness of massively transformed Ti-48mol%Al alloys with tempering were investigated. The results were correlated to the X-ray profile analysis. The integral width of Cu-kα1 net peak especially from γ (111) plane related well to the hardness change. Hall plots suggested that lattice strains are released by spheroidizing with the recovery at low temperature and then small particles grow at higher temperatures, as might support the microstructural change. The small particle size is therefore presumed to be the controlling factor for the hardness. Macro stress is shown not to affect the hardness as much.
Techniques for the Determination of Particle Size and Texture in Retained Austenite / Martensite Microstructures and Interpretation of the Measurements
Authors: Makinson J. D. , Weins W. N. , Xu Y. , Medlin D. J. , Lawrence R. V.
Published: March 2019

The measurement of retained austenite is important in the analysis and quality control of asmanufactured steel components, as well as to the evaluation of components returned from service. The amounts of retained austenite are most accurately measured using x-ray diffraction techniques where the integrated area under the austenite and martensite diffraction peaks from a sample are determined. In addition to quantitative information about the amount of each phase, however, the raw x-ray diffraction data contains other information that may be useful in evaluating the condition of a steel component. The diffracting particle size of both the martensite and austenite phases, and the presence and degree of preferred orientation in both phases can be calculated from the basic four peak retained austenite x-ray scan. This information, in conjunction with knowledge of the amount of retained austenite present, may be used to determine information about variations in materials and manufacturing processes as well as changes due to service. If the residual stress in both phases is also measured, additional conclusions can be made regarding changes due to processing and service. The theoretical and experimental aspects of these measurements are reviewed data from a case history in which these types of measurements were used to determine changes due to processing and service are presented.
What Can Crystallography Tell us About the Intermediate Range Order in Borate Glasses?
Authors: Wright Adrian C. , Vedishcheva Natalia M. , Shakhmatkin Boris A.
Published: March 2019

Crystallographic data for a wide range of crystalline borates are used as a basis to propose a set of topological criteria for the formation of vitreous borate networks, taking into account the topological degrees of freedom necessary for conventional glass formation. It is shown that considerable insight into the structural criteria for the formation of borate networks can be gained by studying the arrangements of superstructural units found in the various crystalline borates.
Structural Characterization of Thin Films by X-Ray Diffraction and Reflectivity
Authors: Brower Daniel T. , Medower Brian S. , Huang Ting C.
Published: March 2019

X-ray polycrystalline diffraction was used to track progress toward improving the structural properties of SrS:(Eu,Sm) thin films. These thin films are used as the active layer of the ETOM (Electron Trapping Optical Memory) media. In this study conventional x-ray diffraction and x-ray reflectivity were used to evaluate the effect of two deposition parameters on film structures. Line broadening analysis performed using the Warren-Averbach technique showed the beneficial effects of a hydrogen sulfide reactive atmosphere and the RF magnetron sputtering technique on crystallite size and microstrain. A factor of five improvement in crystallite size and a factor of two reduction in microstrain was observed. Film thickness, density, and interfacial and surface roughnesses were determined for two SrS thin films. The sin2Ψ technique was used to determine the in-plane biaxial stress for two films prepared by different deposition techniques. These films exhibit inhomogeneous stress states with an average stress of less than IMPa.
Inhomogeneous Deformation in Thin Films
Authors: Noyan I. C. , Goldsmith C. C.
Published: March 2019

Residual stresses are a major factor in the reliable operation of multi-layer thin film structures. These stresses may form due to defect incorporation during deposition, recrystallization, second-phase precipitation, thermal coefficient of expansion (TCE) mismatch, etc., as well as local plastic flow, delamination or cracking. In the literature, residual stresses are usually assumed to be constant in the plane of the film. This assumption is sometimes implicitly made, as in the cases where only two psi-tilts are used in the stress determination with the sin2Ψ analysis.

In this paper, we will review the possible causes of heterogeneous stress distributions in thin films and discuss their impact on x-ray stress determination techniques using some new data from W films.
Depth profiling by Xrf with Variable Beam Geometry Applied to Thin Films in the Nanometer Region
Authors: Ebel Horst , Svagera Robert , Hobl Robert , Kugler Werner , Nguyen Hung Danh
Published: March 2019

Standard applications of quantitative XRF are determinations of composition of bulk specimens, composition and thickness of thin multielement layers and thickness of thin element layers. The theoretical background was given by Sherman, and Shiraiwa and Fujino Numerous approaches like empirical coefficients and fundamental parameters were developed and deliver valuable results. Extending the methods to a quantification of very thin layers consisting of more than one chemical element, it becomes more and more complicated to split the solutions into thickness and composition. The explanation is given by the improving validity of the linear approach for the measured signals in dependence on thickness and composition due to the thin layer approximation exp(x)≈l+x. This leads finally to the finding that measured characteristic signals are proportional to the product c-t, where c represents the concentration of the chemical element under investigation and t the thickness of the layer.