bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermal Stress Relaxation in Vapor Deposited Thin Films
Authors: Noyan I. C. , Goldsmith C. C. 
Published: March 2019

AbstractResidual 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

AbstractA 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

AbstractSimulated 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.
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.
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

AbstractGrazing 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.
Development of a Numerical Procedure for Determining the Depth Profiles of X-Ray Diffraction Data
Authors: Zhu Xiaojing , Predecki Paul 
Published: March 2019

AbstractA 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

AbstractThe 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

AbstractX-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

AbstractA 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.
Mathematical Modeling of XRF Matrix Correction Algorithms With an Electronic Spreadsheet
Authors: Klimasara Anthony J. 
Published: March 2019

AbstractIt 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

AbstractImprovement 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

SummaryIn 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,
Characterization of Thin by X-Ray Fluorescence and Diffraction Analysis
Authors: Huang T. C. , Parrish W. 
Published: March 2019

This paper presents a comprehensive study of various applications of x-ray fluorescence and diffraction techniques for the characterization of thin films. With the proper use of x-ray instruments and techniques, a fairly complete understanding of the chemical and physical structure of thin films was obtained. The x-ray fluorescence (XRF) method was used for the determination of composition, mass-thickness, and density. The x-ray diffraction (XRD) method was used for structural characterization, including: local atomic arrangements of amorphous materials; phase identification, preferred orientation, crystallite size, stacking faults, microstrain, the annealing behaviors of polycrystalline films; and lattice mismatch between the epitaxial film and its single-crystal substrate.In order to obtain a clear picture of the capabilities of the x-ray method and the properties of thin films, a series of carefully selected specimens representing a wide range of compositions and thicknesses was used. A number of practical x-ray techniques, which are valuable for this type of analysis, are also introduced.
Low Temperature X-Ray Diffractometer with Closed Cycle Refrigeration System
Authors: Benedict U. , Cornay Y. , Dufour C. 
Published: March 2019

An assembly consisting of an X-ray tube, a quartz crystal monochromator, and a vertical X-ray goniometer with proportional counter was mounted in a glove box for work with actinide metals and compounds. An evacuated camera containing the expander tube of a closed-cycle cryogenic system was fitted onto the goniometer. A thin layer of the powdered sample was fixed on the end-plate of the expander tube. Beryllium windows were provided in the camera wall for the incident and for the diffracted beam.The cooling camera is suitable for use with thin powder layers or metallic foils. Thicker layers can be studied, but a strong thermal gradient perpendicular to the specimen surface is expected. The camera has been applied to the study of lattice contraction and phase transformation at low temperature In actinide metals and compounds .
J. D. Hanawalt Powder Diffraction Award Lecture
Authors: Frevel L. K. 
Published: March 2019

AbstractA condensed chronology of computer SEARCH/MATCH programs for the analysis of multiphase crystalline powders is presented covering the years 1965 to 1981. For this period the various algorithms for searching a data base of standard powder diffraction patterns, {ds, (I/I1)s}, are predicated on empirical “fingerprint” matching of the experimental powder data, {dν,Iν}, with one or more of the standard patterns. Within the past year an interactive computer SEARCH/MATCH program has been developed based on a structure-sensitive SEARCH procedure.The evolution of computer SEARCH/MATCH procedures undoubtedly will continue and will be influenced by marked improvements in the quality of digitized, machine-readable, powder diffraction data. Three conjectures are offered on future developments in x-ray diffractometry.
Fuzzy Sets and Inverted Search - Two Concepts for Compound Identification in Spectra
Authors: Blaffert Thomas 
Published: March 2019

AbstractThis paper describes a new approach to the interpretation of spectra with ‘fuzzy sets’ and a fast search algorithm for spectrum libraries, using a combination of this theory and the inverse search method. The concepts are applied in a computer program named CIF (Compound identification with Inverted search and Fuzzy sets) which is used in the current application for the interpretation of X-ray powder diffraction signals. The methods are readily applicable to other kinds of spectra such as IR, UV, chromatrography etc.
Suppression of X-Ray Fluorescence Background in X-Ray Powder Diffraction by a Mercuric Iodide Spectrometer
Authors: Nissenbaum J. , Levi A. , Burger A. , Schieber M. , Burshtein Z. 
Published: March 2019

AbstractWe have explored the merits of using a Hgl2 spectrometer as a detector in x-ray diffraction systems instead of a proportional gas counter, or a scintillation counter. The full width at half maximum energy resolution of the HgI2 spectrometer used was about 1.1 keV for the CuKα line (8.1 keV), and about 1.5 keV for the MoKα line (17.4 keV), The energy resolution was utilised to eliminate x-ray fluorescence background from powder diffraction spectra. We demonstrate the suppression of Fe x-ray fluorescence in diffraction patterns of ErFe03 obtained with a Cu x-ray tube, and of Y x-ray fluorescence in diffraction patterns of Y2O3 obtained with a Mo x-ray tube. The peak height to background ratios were improved by about an order of magnitude in both cases.
Multiphase Quantitative Analysis of Colorado Oil Shales Involving Overlap of the Diffraction Peaks
Authors: Smith D. K. , Sterner S. M. , Kerrick D. M. , Meddaugh W. S. 
Published: March 2019

AbstractThe method of intensity ratios can be used for quantitative x-ray diffraction analysis even when none of the diffraction peaks of any phase can be individually resolved. The method uses intensity values from a finite number of discrete integration intervals and appropriate reference-intensity-ratios measured on a set of reference samples to yield a best fit composite pattern that is matched to the unknown by least-squares refinement. Solid-solution phases are analyzed by using multiple reference patterns and determining the best choice during the pattern matching procedure. The method may be extended easily to employ whole diffraction traces by using a large number of small intervals.
Wall Effect and Detection Limit of the Proportional Counter Spectrometer
Authors: Järviner Marja-Leena , Sipilä Heikki 
Published: March 2019

AbstractThe detection limit of the proportional counter spectrometer is determined by the low-energy background caused by the wall effect. The choice of the filling gas of the proportional counter has been studied to minimize the background. Detection limits (3σ) for different elements have been calculated. Theoretical results have been compared with the experimental value obtained with Cd-109 and Am-24l excitation. The results are applied to the analysis of metal concentrations in oil samples and mapping the contents of zinc in the bark of living trees with a portable XRF-analyzer.
XRFA of Carbon in Steels
Authors: Weber F. , Mantler M. , Wariwoda L. 
Published: March 2019

SummaryA set of standard samples consisting of low alloy steels, tool steels and a graphite standard was prepared carefully for measurements by polishing (down to 0.3μm alumina powder) and cleaning of the surfaces. Photographs from optical and scanning electron microscopical images were taken in order to provide information about the microstructure. The measured carbon fluorescent intensities are interpreted in view of this information as well as compared to calculated data based on fundamental parameter models. Thereby excitation by iron and carbon photoelectrons as well as secondary enhancement effects by iron K and L lines and other matrix elements were taken into account.Results suggest that the count rates are not only a function of the total carbon content, but also of graphite segregations and to some extent of the specimen preparation procedure. Graphite particles are easily washed out and the little remaining holes may remain partially covered with carbon or filled with polishing residuals, which leads to reduced count rates.
An Automated On-Stream XRD Analyser for Process Control in the Phosphate Industry
Authors: Engelbrecht Johann P. , de Bruyn S. W. , de Villiers Johan P.R. 
Published: March 2019

AbstractA dedicated on-stream X-ray diffraction (XRD) system for the analysis of rock phosphate-bearing slurries was configured to the requirements of industry for process control. The slurry-handling system includes a multiplexer, header tank, de-aerator, sample splitters and two windowless sample presenters. The x-ray system is comprises a line-focus molybdenum anode X-ray tube, two pyrolytic graphite primary-beam monochromators, two vertical fixed-geometry goniometers, and a simultaneous four scintillation-detector system. The X-ray beam is transmitted through the slurry curtains so that the forward diffracted X-ray intensities of apatite (francolite) and quartz are measured simultaneously. Data obtained by the on-stream XRD analyses of apatite and quartz in rock phosphate from the Florida area in the USA are presented. Lower limits of detection in the order of 0.1 per cent can be achieved for both the apatite and quartz in slurries containing 30 per cent solids. The solids content is a variable that must be known if feeds, tailings, and concentrates are to be measured using a universal algorithm. It can be calculated from the total mineral content of the slurry or from density measurements.
Study of Thin Films and Multilayers using Energy-Dispersive Diffraction of Synchrotron Radiation
Authors: Cernik R. J. , Clark S. M. , Pattison P. 
Published: March 2019

AbstractWe present the results of a preliminary study of the use of polychromatic synchrotron radiation in energy-dispersive mode for the rapid characterization of thin film and multilayer materials. This technique takes advantage of the high intensity and excellent collimation properties of white beam synchrotron radiation. The glancing angle diffraction geometry allows structural depth probing as well as enhanced signal-to-noise by suppressing substrate contributions. The technique was successfully applied to metallic films a few hundred Angstroms thick, and to W-C multilayers.