bluuebunny/crossref_metadata_2025 huggingface dataset:
Residual Stress Measurements in Inconel Alloy 600 Tubing Using an Advanced X-ray Instrument and Cr Kβ Radiation
Authors: Ivkovich D. P. , Ruud C. O. , Snoha D. J.
Published: March 2019

Residual stresses in an inconel alloy 600 U-bend tube, used in heat exchangers in nuclear reactors, were studied using an advanced x-ray instrument developed at The Pennsylvania State University. The work funded by the Electric Power Research Institute (EPRI) mapped both the axial and circumferential (hoop) stresses on the outside surface of the tube. The residual stresses, inherent in the fabrication of the U-bend tubes, are a major contributor to stress corrosion cracking.
X-ray Fractographic Approach to Fracture Toughness of AISI 4340 Steel
Authors: Hirose Yukio , Yajima Zenjiro , Tanaka Keisuke
Published: March 2019

X-ray diffraction observation of the material internal structure beneath fracture surfaces provide fracture analysists with useful information to investigate the conditions and mechanisms of fracture. X-ray fractography is a generic name given to this technique. In the present study, the residual stress on the fracture surface of the compact tension specimens for toughness tests was measured by X-ray diffraction. The effects of notch-tip radius and tempering temperature on the fracture toughness are discussed based on the results of X-ray fractography and fracture micromechanisms.
Strain Measurements on Single Crystals and Macrograins with the Aid of an Automated Phi-Psi Goniometer
Authors: Pathiraj B. , Koster H. , Nijssen A. M. , Willemse P. F. , Kolster B. H.
Published: March 2019

A back reflection goniometer with possibilities of Φ and Ψ rotations of the specimen was developed for stress-strain analysis in single crystals and macrograins and was completely automated. A computer software in PASCAL language was developed. The system is capable of i) optimising the Φ, Ψ and 2θ positions for a reflection, ii) scanning all the specified reflections one after another, iii) determining the lattice spacings after applying suitable corrections to the intensity data and iv) correcting the lattice spacings for temperature variations. Experimental results of measurements on an aluminum single crystal in annealed and plastically deformed conditions are presented to indicate the speed, reproducibility and accuracy of measurements. Principal sources of errors and their control in the developed system are discussed.
The Quality of X-ray Diffraction Standards for Phosphate Minerals and the Degree of Success in Computer Identification
Authors: Blanchard Frank N.
Published: March 2019

Sixty-five years ago Hull first described X-ray powder diffraction as a means of phase identification, and 45 years ago Hannawalt and co-workers compiled the first catalogue of powder diffraction patterns, which has evolved into a file of about 44,000 patterns (the X-ray Powder Diffraction File or PDF). The Hannawalt method of manually searching the PDF is a time-tested, effective tool in seeking a match between an unknown pattern and its correct counterpart(s) in the PDF. Recently, computerized powder diffractometers with software to perform data reduction and search the PDF have become relatively common, and these systems offer tremendous potential for rapid and accurate phase identification in simple and complex systems where the data base may include 44,000 patterns.
High Temperature XRD Studies of Selected Carbonate Minerals
Authors: Iyengar S. S. , Engler P. , Santana M. W. , Wong E. R.
Published: March 2019

Thermal analysts have exploited the sensitivity of carbonate mineral decomposition to furnace atmosphere as a diagnostic tool for identifying and quantifying these minerals in mixtures and solid solutions (1-3). However, thermal analysis techniques alone cannot reveal information about the reaction products after each thermal event. In-situ high temperature x-ray diffraction is one technique that can identify these products. Using this technique, Kissinger et al. (4) identified the reaction products of the thermal decomposition of reagent grade FeCO3 (siderite) and MgCO3 (magnesite). However, the thermal behavior of analytical reagent grade carbonates differs from natural minerals (1). Milodowski and Morgan (5) used in-situ XRD to investigate the thermal behavior of the dolomite-ankerite series.
Fundamentals of X-ray Spectrometric Analysis Using Low-Energy Electron Excitation
Authors: Romand K. J. , Gaillard F. , Charbonnier M. , Urch D. S.
Published: March 2019

In the field of material analysis and characterization interest has considerably shifted over the last few decades from bulk to surface and very thin film problems. At the present state a wide range of surface analytical techniques - such as x-ray photoelectron (XPS), Auger electron (AES), secondary ion mass (SIMS), ion scattering (ISS) spectroscopies - have become available but every one of them exhibits specific analytical features and information content. Within the context of this paper the main parameter to be considered is the information depth i.e the layer thickness from which the majority of information-bearing particles escape and hence are detected. For XPS and AES, this parameter is associated with the mean-free path of photoelectrans or Auger electrons and typically is in the range from 0.5 to 4 nm. In SIMS the ejected secondary ions are emitted from the outer 2 or 3 atomic layers (i.e. from about 1 nm) while the single-collision binary process occuring in ISS is restricted to atoms from the top most atomic layer (0.2-0.3 nm).
Quantitative XRF Analysis Using the Fundamental Algorithm
Authors: Rousseau Richard M.
Published: March 2019

A modern theoretical method using the Fundamental Algorithm to correct for matrix effects in X-Ray Fluorescence (XRF) analysis is described. This powerful quantitative method combines the practical flexibility of influence coefficient concepts and the theoretical exactness of the fundamental parameter technique. This method is in full agreement with the treatment of the physics as proposed by Sherman and can be applied to the analysis of any sample types. It offers the maximum of accuracy limited only by the quality of sample preparation. The special calibration procedure associated with the Fundamental Algorithm is explained. This procedure allows the matching of theoretical formalism to experimental data of each individual laboratory. Finally and obviously, this approach requires a computer program to be applied. Some important guidelines are given to help XRF analysts to select the XRF program appropriate to their needs.
Drift in Energy Calibration of Energy Dispersive X-ray Fluorescence Analyzers and Its Correction
Authors: Liu Zhaogui
Published: March 2019

It is to be expected that drift will occur in the energy calibration of Energy Dispersive X-Ray Fluorescence Analysis (EDXRFA) spectrometers. The error thus caused in the measured x-ray intensity is evaluated in this paper. In order to minimize the error, two steps are necessary. The first is to make a new energy calibration to follow the trend of the drift. The second step involves moving the regions of the characteristic peaks to accommodate the drift. Software has been developed to accomplish both steps automatically.
High-Temperature Displacement Measurement Using a Scanning Focused X-ray Line Source
Authors: Jordan E. H. , Canistraro H. A. , Pease D. M. , Brewe D.
Published: March 2019

A non-contacting displacement measuring system utilizing focussed x-rays is being developed for use in hostile environments. Ultimately, this method will be used to measure mechnical strain under adverse conditions such as high temperatures, flame, cutting fluids, and gases with high velocity and pressure gradients. The foundation of the technique is the use of xrays, which are immune to the various environmental factors mentioned above. The proposed system uses a highly focussed, intense x-ray line which is scanned across markers that fluoresce secondary radiation. This secondary radiation level is then monitored using a photon detector and marker-focussed line overlap can be discerned. These targets can be used as fiducial markers demarcating a gage length, and the change in pointing angle of the focussed beam at target overlap is used as a measure of relative displacement. The present experimental systemcan consistently resolve 1.27 microns at ambient conditions, and 2.54 microns have been measured at a target temperature of 1900 de-grees F through an open flame. Given the performance of the current apparatus, equipment improvements should permit increases in resolution by a least a factor of 10 and measurements at much higher temperatures are possible.
Trace Element Analysis of Rocks by X-ray Spectrometry
Authors: Chappell Bruce W.
Published: March 2019

Undoubtedly the most important applications of X-ray fluorescence spectrometry (XRF) have been in the analysis of major elements where the technique provides a unique method of measuring the concentration of all elements having Z > 10 with extremely good precision in a wide range of matrices. However, XRF is in addition a powerful method for trace element analysis. In this discussion, the principles of the method for the trace element analysis of rocks are outlined, its capabilities are summarized, and the advantages and disadvantages of the technique are pointed out.
X-ray Fluorescence as a Problem-Solving Tool in the Paper Industry
Authors: Istone William K. , Collier John M. , Kaplan Jay A.
Published: March 2019

Wavelength dispersive X-ray fluorescence spectrometry (WDXRF) is used for many types of routine analysis in the paper industry. Examples of routine elemental analysis include analysis of pigments in papers and coatings, analysis of fuels, and analysis of paper-mill waste. In the central analytical laboratory, however, WDXRF is frequently called upon in unique problem-solving situations. In some cases, these problem-solving applications later develop into routine methods.

In this paper, three examples of WDXRF being used as a problem-solving technique are discussed. These situations are: the determination of the cause of ring formation in lime-kilns, failure analysis of ceramic limekiln linings, and the determination of pigment distributions in alkaline papers.
Measurement of Mass Absorption Coefficients Using Compton-Scattered Cu Radiation in X-ray Diffraction Analysis
Authors: Chipera Steve J. , Bish David L.
Published: March 2019

The mass absorption coefficient is a useful parameter for quantitative characterization of materials. If the chemical composition of a sample is known, the mass absorption coefficient can be calculated directly. However, the mass absorption coefficient must be determined empirically if the chemical composition is unknown. Traditional methods for determining the mass absorption coefficient involve measuring the transmission of monochromatic X-rays through a sample of known thickness and density. Reynolds (1963,1967), however, proposed a method for determining the mass absorption coefficient by measuring the Compton or inelastic X-ray scattering from a sample using Mo radiation on an X-ray fluorescence spectrometer (XRF). With the recent advances in solid-state detectors/electronics for use with conventional powder diffractometers, it is now possible to readily determine mass absorption coefficients during routine X-ray diffraction (XRD) analyses.

Using Cu Kα radiation and Reynolds’ method on a Siemens D-500 diffractometer fitted with a Kevex Si(Li) solid-state detector, we have measured the mass absorption coefficients of a suite of minerals and pure chemical compounds ranging in μ/ρ from graphite to Fe-metal (μ/ρ = 4.6-308 using Cu Kα radiation) to ±4.0% (lσ). The relationship between the known mass absorption coefficient and the inverse count rate is linear with a correlation coefficient of 0.997. Using mass absorption coefficients, phase abundances can be determined during quantitative XRD analysis without requiring the use of an internal standard, even when an amorphous component is present.
Evaluation of the X-ray Response of a Position-Sensitive Microstrip Detector with an Integrated Readout Chip
Authors: Rossington C. , Jaklevic J. , Reid J. , Haber C. , Spieler H.
Published: March 2019

Many of the scientific programs proposed for implementation at existing and future synchrotron radiation sources involve measurement of the spatial distribution of transmitted or diffracted x-ray beams. The design of a general purpose position-sensitive detector for use in such experiments must address several conflicting requirements. Ideally, such a detector would meet the following criteria: high detection efficiency over a wide energy range, large dynamic range in measured photon intensities and response to a wide range of measurement intervals. Existing detector systems only partially meet these requirements, although much work has gone into improving the current technology.
Evaluation of Reference X-ray Diffraction Patterns in the ICDD Powder Diffraction File
Authors: McCarthy G. J. , Holzer J. M. , Syvinski W. M. , Martin K. J. , Garvey R. G.
Published: March 2019

Procedures and tools for evaluation of reference x-ray powder patterns in the JCPDSICDD Powder Diffraction File are illustrated by a review of air-stable binary oxides. The reference patterns are evaluated using an available microcomputer version of the NBS*A1DS83 editorial program and PDF patterns retrieved directly from the CD-ROM in the program's input format. The patterns are compared to calculated and experimental diffractograms. The majority of the oxide patterns have been found to be in good agreement with the calculated and observed diffractograms, but are often missing some weak reflections routinely observed with a modern diffractometer. These weak reflections are added to the PDF pattern. For the remainder of the phases, patterns are redetermined.
X-ray Topography and TEM Study of Crystal Defect Propagation in Epitaxially Grown AIGaAs Layers on GaAs(001)
Authors: Bassignana L. C. , Macquistan D.A. , Clark D.A.
Published: March 2019

Asymmetric crystal topography (ACT) in reflection and transmission electron microscopy (TEM) were used to investigate the crystal quality of both typical GaAs substrates and AIGaAs epitaxial layers grown on these substrates. ACT topographs of large sections of 75mm GaAs wafers revealed the presence of several types of crystal defects. All the GaAs wafers surveyed showed the presence of low angle grain boundaries which usually extended over a significant portion of the wafer. In addition, the well-known cell structure dislocation network was always observed in semi-insulating wafers. Less common but often present were inclusions and precipitates. The n-type (Si doped) substrates showed a typical cross-hatched pattern. ACT topography also easily revealed the crystal damage caused by wafer grinding.

Epitaxial layers of AIGaAs were grown by conventional molecular beam epitaxy on these characterized GaAs substrates. ACT topography was used to examine separately the epitaxial layers and substrate crystals. Layers which were grown below the pseudomorphic limit showed crystal features identical to the GaAs substrate on which they were grown and the substrate was unaffected by the presence of the epitaxial layer. AJAs layers which were grown above the pseudomorphic limit were severely dislocated: TEM confirmed the presence of misfit dislocations at the interface. The substrate in this case also showed the presence of crosshatching indicating the the extension of the dislocation strain field into the substrate.
Lineshape Analysis of X-ray Diffraction Profiles: Polyethylene and Model Copolymers
Authors: Crist Buckley , Howard Paul R.
Published: March 2019

Studies of the shapes of X-ray diffraction peaks from synthetic polymers are still rather uncommon. One probable cause of this situation is the small peak-to-background ratio in most polymer diffraction experiments; it is difficult to achieve precise line profiles for quantitative analysis. Increased utilization of automated data collection/analysis systems and more intense X-ray sources should alleviate this restriction. We suspect, furthermore, that confusion about nomenclature has impeded the acceptance of lineshape analysis for polymers. The peak broadening mechanisms which are generally considered are finite coherence length or crystal size, lattice parameter fluctuation, and displacement disorder of the second kind. Both latter mechanisms have, unfortunately, been referred to as “strains” or “microstrains”. Metallurgists have traditionally expressed displacement disorder as a (length dependent) “microstrain”, and this convention has been adopted in some studies of polymer diffraction. Other work on polymers, however, has termed lattice parameter fluctuation as “microstrain“. The inconsistent use of this term can imply a nonexistent relation between two distinct phenomena.
Substructure-Magnetic Property Correlation in Fe/Ag Composite Thin Films
Authors: Reed C. P. , DeAngelis R. J. , Zhang Y. X. , Liou S. H. , Jacob R. J.
Published: March 2019

A series of nanostructured Fe/Ag metal films were produced at various substrate temperatures to determine their magnetic characteristics. The magnetic coercivity was found to increase with the diffracting-particle size which is process controlled. The films produced at low substrate temperature (<200°C) consisted of small metallic clusters of Ag (<100 Å). As the substrate temperature was increased, the films exhibited increased crystallinity and larger diffracting-particle size. The position of the maximum in the particlesize distribution function and the width of the function increased with substrate temperature.
Thermal Stress Relaxation in Vapor Deposited 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 form due to various causes. Defect incorporation during deposition, rccrystallization, second-phase precipitation, coefficient of thermal expansion (CTE) mismatch, etc., can all cause the formation of residual stress fields. These stress fields can also change during the operation of the device, depending on the temperature excursions seen during the operation. Again, the stress change may be due to any of the factors listed above, brought about by the temperature excursions.

In this paper we examine the formation and relaxation of residual stresses in “blanket” Al, Cu and Ni films subjected to temperature cycling. Comparison of the stress dependency on temperature to the total retained strain (measured by a micro-grid technique) is then used to determine the location of plastic flow within the film.
Residual Stresses in Railroad Car Wheels
Authors: Jo J. , Hendricks R.W. , Swanson R.E. , Foutz R.V.
Published: March 2019

A new failure criterion for discriminating good and bad (overheated) railroad car wheels is proposed using X-ray residual stress data. The procedure for the new discrimination criterion is based on the fluctuations of the azimuthal residual stress in the tread of the wheel. This criterion is based on a maximum likelihood statistical analysis of stress data obtained from six different wheels as determined by x-ray diffraction. Of these locations, the analysis showed the tread, and perhaps a critical point on the top of the flange, to be the most sensitive to residual stress. The variance analysis showed that fluctuations in stress a.l the most sensitive location in the tread to be related to the service history. The residual stresses showed an oscillatory pattern in the hoop direction around the wheels. Extension of the measurement technology to the use of faster residual stress measurements is proposed. To validate our x-ray residual stress data, residual stresses were also measured by hole drilling. Excellent agreement between two techniques was found.
Measurement of Residual Stresses by X-ray Diffraction Near Simulated Heat Affected Zones in Austenitic Stainless Steels
Authors: Iyer V. S. , Hendricks R. W. , David S. A.
Published: March 2019

Simulated heat-affected zones (HAZs) were made in austenitic sta.inless steel specimens using a Gleeble. The samples were heated to temperatures as high as 1100°C by computer controlled resistance heating. By controlling the heating rate, maximum temperature, and cooling rate, a wide range of residual stresses were introduced in the specimens. Stress measurements were made using X-ray diffraction. It was found that significant stress gradients were produced in the simulated HAZs, and that all stresses were compressive in nature, both in the longitudinal and transverse directions. These results are not representative of the residual stresses determined in the HAZs of real welds, thus calling into question some aspects of the role of the Gleeble in such simulations.
Determination of X-ray Elastic Constants in a Ti-14Al-21Nb Nb Alloy and a Ti-14Al-21Nb/SiC Metal Matrix Composite
Authors: Jo J. , Hendricks R. W. , Brewer W. D. , Brown Karen M.
Published: March 2019

Residual stress values in a material are governed by the measurements of the atomic spacings in a specific crystallographic plane and the elastic constant for that plane. It has been reported that the value of the elastic constant depends on microstructure, preferred orientation, plastic deformation and morphology [1], Thus, the theoretical calculation of the elastic constant may deviate from the intrinsic value for a real alloy.
X.R.F Analysis of Steelmaking Slags Using Special Sample Preparation Techniques
Authors: Van de Vrande W. , Cosma D. , Tekatch W.
Published: March 2019

X.R.F. analysis of steelmaking slags has been done routinely since the 1960s. Fused buttons or pressed powdered pellets are used.

Under certain conditions steelmaking slags may contain appreciable amounts of free lime and metallic iron droplets. These can cause gross inaccuracies in the result of the X.R.F. analysis as the normal correction procedures used in X-ray fluorescence techniques can not compensate for them.

A special sample preparation technique as well as appropriate analytical procedures will be discussed. Examples of slags with different levels of free lime and metallic iron will be shown.
Method of Measurement of Mean Concentration for an Element Segregated in Layers by X-Ray Analysis
Authors: Vander I.
Published: March 2019

Traditionally, in X-ray fluorescence analysis for the determination of elemental compositions, the fluorescence is measured from the irradiated side of the sample. The composition measurements obtained by this method are sensitive to a gradient in composition as a function of depth of the element being measured. This report presents a simple method for measuring a mean composition for an element segregated in layers applicable to thin samples so that the fluorescence can be measured on the side opposite to that being irradiated. It is shown that for a particular relation between the angle of incidence of the primary radiation and of the detection angle on the opposite side of the sample that a mean concentration can be measured for an element which is independent of the composition in the separate layers.
Errors in Dual X-Ray Beam Differential Absorptiometry
Authors: Bolin F. , Preuss L. , Gilbert K. , Bugenis C.
Published: March 2019

Errors pertinent in dual beam absorptiometry have been studied. Five areas are given in detail: 1. Scattering, in which a computer analysis of multiple scattering shows little error. 2. Geometrical configuration effects, in which the shape of the sample influences accuracy. 3. Poisson variations, in which dosage and statistical error are minimized. 4. Absorption coefficients, in which variations in compilations are examined. 5. Filtering, wherein is shown the need for Kβ filtering. A zero filter system is outlined.
On Energy Dispersive Properties of the Proportional Counter Channel
Authors: Sipilä H. , Kiuru E.
Published: March 2019

This paper presents an investigation on factors which contribute to the properties of the proportional counter system. The effect of the counter and the electronics has been discussed. A low noise detector preamplifier combination has been described. The resolution has been measured as a function of gas gain for the mixtures Ar-CH4, Ar-CO2, Ar-Xe and Ne-Ar. The gas gain ranges from 5 to 100. It has been found for all mixtures that the resolution of the detector improves slightly with lowering the gas gain. The recovery is most effective in Ne-Ar mixtures. The noise of electronics prevents the use of very low gas gains and for that reason determines the optimum gas gain regarding the resolution.
A Radioisotope On-Stream Analyzer for the Mining Industry
Authors: Hifetala M. , Viitanen J.
Published: March 2019

A distributed on-line analyzing system has been developed for automatic multielemental analysis of mineral slurries and solutions. The elements to be measured should be heavier than potassium. The system consists of measuring probes, a communication loop and a minicomputer with its peripherals. The measuring probe may either be directly immersed into the process stream or it is used with a sample cell in a by-line stream. Measuring probes are located at separate positions in the process. The measurement is based on X-ray fluorescence radiation which is excited with a sealed radioisotope source. The radiation is detected with a sealed high resolution proportional counter without filters. Spectrum stripping is based on reference samples which are measured in a computer controlled sequence in the same geometry as the sample. Thus possible instabilities in gain and resolution are under control. Chemical assays and slurry density are calculated from fluorescence and backscatter intensities. The minicomputer also controls the probes in the system and gives reports.
Getting Accurate Intensity Values from Energy Dispersive X-Ray Spectra Using Fixed Energy Windows
Authors: Russ John C.
Published: March 2019

Most integration of peaks in energy dispersive X-ray spectra is carried out using fixed energy “windows” or “regions of interest” set in terms of channels in the multi-channel analyzer (whether of the hardware or software based type). This gives rise to two sources of error that can be very significant hut can each be corrected with modest calculation effort.
Software for XRD
Authors: Johnson Q.
Published: March 2019

PC software for XRD is strongly influenced by the cost of the hardware. Contrasted to mainframe and mini platforms, PC's are essentially free, or at least much less expensive than maintenance contracts for the hardware we've used in the past. But when we get our own computer, we discover that much more time goes into tasks others did before such as system maintenance. PC software needs to be simple to use yet very powerful, so we can recover some of that time. Changes have been made. Much more remains to be done and that change is coming fast.
The Use of PCs for AB Initio Structure Determination From Powder Diffraction Data
Authors: Louër Michèle , Louër Daniel
Published: March 2019

The determination ab initio of crystal structures from powder diffraction data has been the most striking advance of modern powder crystallography. It is a consequence of the major developments occurred in instrument resolution, powder pattern indexing and Fitting techniques, e.g. the problem of peak overlap resulting from the collapse of the three dimensional pattern into one dimensional powder diffraction data has been circumvented by the advent of the Rietveld method. A structure analysis starting from scratch involves successive stages from the collection of high quality powder diffraction data to the refinement of the atomic coordinates by the Rietveld method. Since the pioneering work by Werner and co-workers a number of crystal structures solved from powder diffraction data, collected with synchrotron and conventional sources have been reported. With the growing development of this important application of the powder method, integrated softwares for solving crystal structures are now of interest, and a number of programs are available for the analysis of the different stages of a structural study. These programs combine computer routines for the treatment of powder diffraction data and routines used in conventional structure determination from single crystal data. Most of these programs have been listed in the Powder Diffraction Program Information 1990 Program List. Owing to the efficiency of modern personal computers, solving a crystal structure ab initio from powder diffraction data can now be carried out with a desk computer.
Applications of Profile Analysis for Micro-Crystalline Properties From Total Pattern Fitting
Authors: Louër Daniel
Published: March 2019

The characterization of finely divided and structurally imperfect solids is required in the study of many classes of materials, e.g. ceramics, catalysts, decomposition products. Diffraction line broadening is influenced by the microstructure of the solid and is a valuable technique for a unique characterization of a material in terms of size and morphology of crystallites (a region over which diffraction is coherent) and imperfections (microstrains, d- spacing fluctuations, stacking faults, etc). The extraction of these features has traditionally been based on the study of individual diffraction lines, which restricts the analysis to a limited number of directions of diffraction vectors. The complexity of most powder patterns has been a serious impediment to the widespread use of the procedure for detailed microstructural characterization. The advent of fitting techniques, with the use of structural information (Rietveld method) and without structure model (pattern decomposition method) have extended the frontiers of diffraction line profile analyses. In the Rietveld method it has been recommended to have a prior knowledge of the origin and lattice direction dependences of the imperfection effect before embarking in the modelling of line broadening through the pattern. This modelling can be carried out with pattern decomposition methods, which provide individual diffraction lines for a subsequent study of microstructural properties. Several aspects of this technique, performances, limitations and practical problems are reviewed and discussed. Applications to oxides with high specific surface-area are used to illustrate the detailed microstructural information contained in a powder diffraction pattern.
Application of ODF to the Rietveld Profile Refinement of Polycrystalline Solid
Authors: Choi C. S. , Baker E. F. , Orosz J.
Published: March 2019

The Rietveld profile refinement method is probably the most popular technique used for the crystallographic characterization of materials including crystal structures and phase analysis, but it has been used mostly with ideal powder sample, not with textured polycrystals, because effects of strong and complex textures. Most technological materials are fabricated by using thermo-mechanical forming processes, which inevitably produce strong and complex preferential orientations of the crystallites. Consequently, the diffraction patterns of a given technological material are not unique but vary considerably with the measuring direction, with intensity variations as large as factors of hundreds, depending on the degree of texture. The texture effect on the diffraction pattern of a certain sample direction is directly proportional to the pole density of the corresponding inverse pole figure, which can be obtained from the three-dimensional orientation distribution function (ODF) of the material. The ODFs of materials with high crystal symmetry, such as cubic, hexagonal, tetragonal, and orthorhombic, can be determined quite precisely, using modern texture analysis techniques (for example, Bungel, Wenk, and Kallend et al.). The pole density distributions of the inverse pole figures can be used in the diffraction profile calculation of a highly textured sample.
Enhancing XRPD Pattern Quality With Line-Profile-Fitting in Multiphase Systems
Authors: Kimmel G. , Sariel J. , Dahan I. , Nathan S. , Admon U.
Published: March 2019

In the past the powder diffraction data where presented as d-I sets as obtained experimentally and systematic errors were utilized only for the derivation of the unit cell parameters. This attitude was justified by the fact that the major work of XRPD made by Debye-Scherrer camera and it was assumed that most users would obtain the same systematic errors. Nowadays, diffractometry has taken over, and the diffractometers have lower systematic errors, which can minimized by calibration. Thus, they are now preferred. There are many phases which can be used as standards, but only four were selected, namely, Si, Ag, W, and mica (FP), which can easily be obtained as pure substances, have a limited number of diffraction lines and the distribution of intensities along 2θ is good. The calibration is made by fitting a polynomial which correlates the standard experimental peak positions versus the expected (calculated) values. However, while on the one hand, the more peaks which are used, the better the fit which can be achieved; on the other hand using a standard with many peaks enhances the probability for interference with the examined specimen peaks. Thus, it was decided to determine each line position by line profile fitting as was recommended elsewhere. In order to derive real observed data we do not link the diffraction lines between themselves by global structural or tine shape parameters. Thus, local variations in line profile parameters are treated. In the line-profile-fitting method suggested here the final structural details (atomic positions) are not required. Similar method have been used in the past for structure analysis, unit-cell refinement, and broadening analysis of pure substances. It was found that using the suggested method yields accurate unit cell parameters for each individual phase in the polyphase mixture. Several systems will be demonstrated in this work.
Experimental Comparison of Widely Differing Lattice Parameters
Authors: Bowen D. K. , Tanner B. K. , Hudson J. M. , Pape I. , Loxley N. , Tobin S.
Published: March 2019

We report the implementation of two new methods of accurate comparison of lattice parameters against a silicon standard using a high resolution X-ray diffractometer. The double axis method uses a specimen rotation stage which set the limit of reproducibility (at 3 sigma) to 3 parts in 105. An application of the technique is illustrated in measurements of the zinc concentration in Cd1-xZnx Te to an accuracy of 0.1%. The triple axis technique uses beam conditioner and analyser crystals to define the incident and diffracted wave vectors. In measurement of the lattice parameters of InAs, we found a precision of 1 part in 105 and traceable accuracy of a several parts in 105.
The Effects of Using Long Soller Slits as “Parallel Beam Optics” for Gixrd on Diffraction Data
Authors: Eatough Michael O. , Gochner Raymond P.
Published: March 2019

Grazing incidence x-ray diffraction (GIXRD) using long soller slit assemblies and a flat crystal monochromator, sometimes referred to as thin film optics, are used to study poly crystal line thin films, polymers, metals, etc. The unique ability of GIXRD to characterize crystalline materials as function of depth and provide accurate strain measurements has lead to the growing popularity of this technique. This non-focusing pseudo-parallel beam geometry can produce various effects on diffraction data which can make interpretation difficult Artifacts such as peak splitting, kα2 distortion, and peaks which shift dramatically as a function of grazing incidence angle are observed when using GIXRD. These artifacts can be related to grazing incidence angle, the divergence of the soller plates, the thickness of the soller plates, the substrate material, and the type of monochromator used. This paper briefly describes some of the topics discussed at the 1992 & 1993 Denver Conferences workshops on parallel beam optics.
Characterization of TiN Film by XRD and XRF
Authors: Kimmel G. , Politi L. , Wieder T.
Published: March 2019

TiAIN is a protective coating for cutting and reshaping tools, since it reduces wear, increases the cutting velocity of cutting tools, and increases the lifetime of reshaping tools. Thus many investigators studied the structure and properties of thin TiN films1-6. Due to the complicated geometry of the tools, the coating thickness may vary at different locations on a tool. For quality assurance thickness measurements are necessary. In this work-as a first step-only a simple geometry was considered.
Development of a Numerical Procedure for Determining the Depth Profiles of X-Ray Diffraction Data
Authors: Zhu Xiaojing , Predecki Paul
Published: March 2019

A numerical procedure is described and demonstrated for determining z-profiles from measured τ-profiles of diffraction data such as may be obtained by grazing incidence x-ray diffraction (GIXD). The z-profile was approximated by a piece wise linear function and the problem of solving the integral equation for the z-profile was thus converted to one of solving a set of linear equations. With a sufficient number of the linear pieces, the z-pTofile could be accurately determined. The procedure and its sensitivity to data errors was tested with several arbitrarily chosen known functions. It was found that when errors were introduced into either the τ-profile or the sample thickness D the resulting z-profiles become oscillatory.
Analysis of Multi-Layer Thin Films by XRF
Authors: Kaufmann M. , Mantler M. , Weber F.
Published: March 2019

The characterization of multi-layer thin film properties, such as thicknesses of layers or concentrations of elements, using the fundamental parameter method is discussed. Experimental results are shown for repetitive multi-layers of up to 80 layers. Furthermore the impact of using different characteristic lines on the information depth and the resolving power is discussed for single layers and repetitive multi-layers. Finally, thin films containing light elements are presented; in this case the conventional fundamental parameter theory fails to provide accurate results, perhaps due to the neglect of the impact of the secondary excitation by photoelectrons.
Residual Stress Analysis of Different Microstructures in Alumina Microelectronic Substrates
Authors: Ward A. , Venzant K.L. , Hendricks R.W.
Published: March 2019

X-ray residual stress analysis was used to investigate the role of various phases in the formation of residual stress in laser-scribed alumina microelectronic substrates. Previous work by our group shows that the stress induced in the vicinity of a laser-scribe line is 20 to 50 percent of the modulus of rupture of this multiphase material. Our concern with the resulting stress is fracture of the substrate during subsequent firing processes and in-service fracture of the finished microelectronic device.

The phases investigated, in addition to the alumina matrix, included a glassy phase (7% by volume), a spinel structure (3%), and porosity (4%) in 96% alumina. Electron probe microanalysis (EPMA), electron spectroscopy for chemical analysis (ESCA). scanning electron microscopy (SEM), and quantitative metallography were used to characterize the microstructure and composition of these phases. A Nd:YAG laser was used to scribe lines which raised the state of stress in the substrate.

X-ray residual stress analysis shows that a uniform residual stress exists across the laser-scribed substrate, contrary to expected results. X-ray composition analysis suggests that the spinel phase of the material is vitrified in the heat affected zone of the laser scribe. The formation of this brittle glass phase, mainly at triple points and grain boundaries, may act as a pathway for inter-granular fracture and lead to subsequent failure of the finished microelectronic device.
Size/Strain Broadening Analysis of SRM 676 Candidate Materials
Authors: Kalceff Walter , Cline James P. , Von Dreele Robert B.
Published: March 2019

A project was undertaken to compare the Williamson-Hall and Fourier teclrniques for analyzing particle-size and micro-strain induced x-ray line profile broadening. The four alumina powders analyzed in the study were the candidates from which SRM 676, a quantitative analysis Standard Reference Material, was chosen. SRM 660 (LaB6) was used to determine the instrument profile function, IPF. However, difficulty was encountered in fitting an appropriate mathematical model to the IPF data; this prevented the application of Fourier analysis methods and restricted the number of profiles that could be analyzed with the Williamson-Hall method. The size/stain data compared favorably with other microstructural data collected on these specimens.
Microcrystalline Properties of Quartz by Means of Xrpd Measures
Authors: Berti Giovanni
Published: March 2019

Different diffraction patterns were compared one to the other in order to evaluate the contribution of different effects: Thus, in order to arrive at observing true differences between the patterns, “Diffraction Instrumental Monitoring” was adopted to assess reproducibility, stability, as well as differences in the instrumentation set up. To this end aberrations affecting peaks centroid position and variance were taken into account, Moreover the variation of variance of single peaks was analysed to achieve information on microcrystalline properties of real crystalline lattices.
Txrf Semiconductor Applications
Authors: Hockett R. S.
Published: March 2019

This is a review of Total reflection X-Ray Fluorescence (TXRF) applications for semiconductors. This review is limited to surface analysis of contamination for semiconductors and does not include chemical analysis in semiconductor processing. TXRF for surface analysis is a relatively new technology. One of the first publications occurred in 1986 using synchrotron radiation. Publications using commercially available TXRF instruments for semiconductor applications began in 1988. Today there are on the order of 100 TXRF instruments worldwide in the semiconductor industry. Since 1988 there have been about 100 publications in this field, but this number does not include numerous abstracts and publications in Japan where the majority of the commercial instruments are found today. The commercial instruments were developed for the primary application of characterizing the cleaning of planar silicon wafers, however, numerous unforeseen applications were developed by users and many of those applications are reported here. In essence TXRF has much broader application today in the semiconductor industry than supporting the cleaning of silicon wafers.
Mathematical Modeling of XRF Matrix Correction Algorithms With an Electronic Spreadsheet
Authors: Klimasara Anthony J.
Published: March 2019

It will be demonstrated that the Lachance-Traill, and Lucas-Tooth and Price matrix correction algorithms can easily be applied to spreadsheet stored XRF data.

The structure of spreadsheet stored data in Quantitative XRF Analysis, the utilization of built-in spreadsheet functions essential for data processing and the utilization of Spreadsheet Graphics for plotting of corrected and uncorrected XRF data will be presented.

Development of modern Electronic Spreadsheets has reached the point where they can readily be used for almost any type of laboratory task, including: Data Plotting, Statistical Data Analysis, Report Writing and Publishing, Slide Presentations, etc. This valuable tool can easily be added to older equipment that usually lacks sophisticated XRF software. It can also become an auxiliary tool to modern XRF spectrometers equipped with advanced XRF software.

The spreadsheet approach gives the analyst freedom of choice to process data according to personal/analytical preferences circumventing the rigidity of software supplied with the equipment. The spreadsheet approach also possesses educational value since it presents the basic ingredients of Matrix Correction in clear and concise table fashion. Addrtionaliy, the spreadsheet program is an excellent tool for demonstrating and evaluating different matrix correction models commonly used in X-ray Spectroscopy.

It will also be shown tliat Spreadsheet Graphics are capable of handling the two-theta scans of XRF or XRD data gathered from older DEC/PDP-11 based Rigaku Equipment. This results in excellent hard copies of the two-theta scans, regardless of the output device.

A mathematical background leading to the spreadsheet approach was partially presented in the paper “A mathematical comparison of the Lachance-Traill Matrix correction procedure with statistical multiple linear regression analysis in XRF applications” (41st Annual Denver X-ray Conference, Colorado Springs, 1992).
New Empirical Regression Type Algorithm and Software for High Precision XRF Spectrometry
Authors: Smolniakov V. I. , Koltoun I. A.
Published: March 2019

Improvement of the empirical regression type algorithm, based on the well-known canonical form equation by Lachance, for calculations of chemical element concentration and its applications for XRF expressanalysis to control and manage the technological processes on mine manufactures, are considered.

Despite the criticism of regression-type algorithms, because they have no physical sense, they are used successfully in the software of xray quantometers and energy dispersive spectrometers at different plants when it is necessary to analyze the samples with slightly varied matrix for the concentration of the elements of interest very rapidly (2-3 minutes for full analysis of one sample) and with high accuracy (-1% relative error in weight).

Our task was to improve the so-called physics of the algorithm to get the required analytical stability and to account for the random factors which influence measured intensities unexpectedly (heterogeneity of analyzed sample, roughness of its surface, etc.).

The results of the investigations were applied to the samples of apatit-nephelin manufacture. Together with successful solution of the problem, new analytical possibilities for classification of samples according to their mineralogical differences were obtained.

The new XRF empirical regression type algorithm was realized in special software.
Analysis Of Boron And Other Light Elements in Glasses by the Fundamental Parameter Method
Authors: Weber Franz , Mantler Michael , Kaufmann Martin
Published: March 2019

In the current work an attempt was made to apply the fundamental parameter method to the analysis of boron, oxygen, fluorine and heavier components of silica glasses. Experimental results are presented and compared with calculations based on theoretical work. The specimens consist of sets of certified standards which were obtained from Breitlahder company, Germany.

Furthermore, it is shown that the match between the certified compositions and fundamental parameter computations is affected by the quality of available fundamental parameters for the ultralight elements as well as by the underlying mathematical models. Especially in quantitative analysis of these elements, a large variety of secondary enhancement effects must be taken into account. Two major mechanisms have been considered in the presented computations: excitation by fluorescence photons emitted from aiJ available excited atoms, and excitation by photoelectrons ejected after the primary ionization event. Their magnitude exceeds that of the conventional energy region by far and thus uncertainities in the corrective algorithms have a large effect,