Ten compounds are found in the Ba0-Y203-CuOx system. High temperature (≈950-1000°C) phases identified as Ba4Y2O7 , Ba2Y2O5 , Ba3Y4O9 , BaY2O4 , Y2Cu2O5 , BaCuO2+x, Ba3YCu2OZ BaY2Cu05 and BazYCu306+x are formed in this temperature range. In addition, a new compound with composition of 2BaO:CuO, which possibly has a melting point below 950°C, was prepared at 850°C. A summary o£ the crystallographic data of these 10 phases is given. In particular, results of x-ray studies pertaining to four compounds, BazYCu306+x, which is currently the most promising high To' superconductor material, Ba2Cu03 , BaY2Cu05 , and Ba3YCu20Z are reviewed.

Machine parts made of ceramics are usually finished by grinding. Residual stresses as well as defects introduced by grinding will influence the fracture strength and the function of ceramics parts. Although several investigations used the X-ray diffraction method to measure the grinding residual stresses, their grinding conditions were rather limited.

In the present study, sintered alumina ceramics of 99% purity were ground with a resinoid diamond wheel (#140 grain size number) under various grinding conditions. The effects of depth of cut and stock removal on the residual stress was measured with the X-ray method.

Quantitative analysis by x-ray powder diffraction methods has become increasingly important in recent years with the availability of computer-controlled automatic powder diffractometers. All data gathering techniques require suitable reference standards to scale the measured data properly. One means of achieving this scaling is through the reference Intensity ratio which is defined as the intensity ratio of the strongest diffraction maximum of a substance to the strongest maximum of a reference material in a 1:1 mixture “by weight. These ratios may he measured or they may he calculated if the crystal structures of the materials are accurately known.

A modern analytical laboratory of a large corporation manufacturing paper, construction materials and chemicals must be sufficiently diversified in methodology to provide accurate results in the shortest possible time. Among other techniques the implementation of an automated “menu” driven wavelength dispersive spectrometer allowed for the setting-up of a variety of quantitative X-ray fluorescence methods.

A formalism which was proposed by Ruppersberg (1992) for a self consistent evaluation of stress gradients in the case of strongly varying σ33(T) stresses is applied for studying the variation of the stress components with distance z from the irradiated surface of a ground hardened steel plate.

The crystal structures of elements and alloy phases in the B-metal region (B2(Zn) to B5(As) groups) have been classified into phase fields determined by their position in the periodic table. The limited number of equilibrium phases with element-like, disordered crystal structures and of extended terminal solid solutions has been more than doubled by the addition of metastable phases produced by ultra-rapid quenching from the melt (splat cooling). Strong structural correlations exist. Some high pressure phases have been included; in some cases, a qualitative discussion from the viewpoint of pseudopotential theory is given.

Texture (of a polycrystalline sample) means the orientation distribution of the many crystallites in the sample with respect to a coordinate system on the sample, for example the rolling direction. Texture is responsible for many macroscopic properties of materials, for example in metals and alloys in the process of rolling or hot-pressing. It carries importance in many everyday production processes. Also in areas of geological science the texture of the sample, e.g. of the rocks should be known in order to explain geological processes.

Since the development of the first practical electron probe microanalyzer by Castaing and Guinier in 1951, approximately 14 such instruments have been placed in operation throughout the world and at least 15 more are under construction. All of the existing instruments contain the following basic components: (1) An electron beam system, (2) a movable specimen stage, (3) a means for viewing the surface of the specimen, and (4) an X-ray analyzer. The integration of these components into a practical instrument requires certain compromises in the performance capability of the instrument. A critical evaluation of the various approaches to this problem is given and a new electron objective lens is described which results in fewer restrictions on the over-all performance. The basic design of an instrument employing this lens, which will be manufactured by the Applied Research Laboratories, is discussed.

Revised tables of x-ray mass attenuation and absorption cross sections have been prepared for the elements with atomic numbers one to 94 at selected wavelengths of interest to spectroscopists, microprobe users, diffraction workers, etc. The tables are derived from an x-ray cross section compilation to be published during the summer of 1971. The new compilation is a revision of a previous work and provides photoelectric, coherent scattering, incoherent scattering, absorption component of incoherent scattering and total attenuation cross sections for 94 elements for the photon energy range 0.1 keV to 1 MeV (0.0124 Å to 124 Å). The cross sections for energies greater than 1 keV (12.4 Å) were determined from experimental attenuation data and theoretical scattering cross sections calculated using form factors and incoherent scattering functions based on a relativistic self consistent field method. For hydrogen, the photoelectric absorption cross sections were calculated exactly. Least squares procedures were used to interpolate and extrapolate for elements and photon energies where no experimental data were found. Cross sections for the energy range 0.1 keV to 1 keV (12.4 Å to 124 Å) were calculated using nonrelativistic, single electron, self-consistent field theory with Herman-Skillman bound state wavefunctions, A brief description is given of the assumptions and methods used in preparing the revised compilation, and estimated uncertainties in the cross section are reported. Examples illustrating agreement between tabulated values and experimental data are given and a comparison is made with values taken from earlier x-ray cross section compilations.

X-ray diffraction analyses were applied to various pure nickel substrates while exposing them to oxygen at temperatures up to 800 °C. Coefficients of thermal expansion (CTE) were calculated from lattice parameters for both the nickel and the growing surface oxides. Behaviors more complex than the case for single phase bulk solids were observed due, in part, to oxidationinduced strains. The CTE values for such dynamic composite systems are not the same as those for the bulk solids. Thus, for example, the CTE values were found to be dependent on substrate metal thickness. In addition, discontinuities in the CTE's of both nickel and NiO occurred at or near their respective second order phase change temperatures.

I report the experimental setup to obtain an x-ray beam from germanium monocrystal of unusually small angle of vertical divergence of the order of 2 sec. of arc without using any collimator. The production and the properties of the highly collimated beam of x-ray will be described. A rectangular piece of germanium 1” × 1” and of thickness 0.5 mm has been cut with specific orientation of crystallographic planes (111) and (110). The 1” × 1” surface is parallel to (111) planes and the surface of one edge is parallel to (110) planes suitable for Borrmann channelling via (220) planes.

Rietveld X-ray powder diffraction (XRD) and uniaxial stress measurement procedures are being evaluated as a means of correlating the crystalline structure properties of zinc-nickel electroplate with observed plating properties. The study is being performed on a suite of six samples of varying composition (6 to 20%Ni) electrodeposited on mild steel. Rietveld refinement of the XRD data (Rietveld, 1969) has been performed on a specially prepared ingot (9%Ni:91%Zn) to determine the structural parameters and relative abundances for the γ(Ni4Zn22), δ(Ni3Zn22) and η(Zn) phases which could possibly be present in the electroplate. Relative phase abundances were verified by Atomic Absorption Spectrometry (AAS) and electron probe microanalysis (EPMA) image mapping techniques.

The structural parameters for the ingot zinc-nickel phases were subsequently used as initial parameters in Rietveld calculations for the six electroplate samples. Structure refinement of the electroplate XRD data was hampered by extremely high preferred orientation and the corresponding lack of quality diffraction peaks. However, Rietveld refinements produced accurate cell dimensions (which correlate linearly with nickel composition), a means of quantifying the degree of preferred orientation, and crystalline phase verification. For residual stress determination, d-sin2ψ plots were produced for each electroplate sample. The plots were found to be linear for Ni < 12%, allowing calculation of residual stress, and distinctly curved for Ni > 12%.

Fluorescent X-ray spectrographic analyses have been made for the oxides Fe2O3 caO, MgO, K2O, TiO2, and MnO on samples of amphibolite rock. In addition, the above oxides and SiO2 and Al2O3 have been determined in a suite of constituent hornblendes from these rocks.

Classical wet chemical analyses of materials of the same minera logical composition as the samples are used to establish the working curves. This eliminates the necessity for Internal standardization or other treatment of the samples. The only sample preparation involves extremely fine grinding before analysis.

Precision of the analyses is equivalent to, or better than, that achieved by wet chemical methods.

Developments during the past few years in solid-state radiation detectors and low-noise electronics employing field-effect transistors operated at cryogenic temperatures have resulted in the availability of high-resolution energy-dispersive spectrometers for a variety of applications in x-ray spectrometry. Using pulseamplitude analysis techniques, these spectrometers make it possible to obtain multi-elemental analyses on a routine laboratory basis employing x-ray fluorescence techniques. The combination of these spectrometers with small, inexpensive on-line computer data systems makes It possible to obtain rapid on-line qualitative and quantitative analysis of samples in the laboratory and in special field applications. A general review of the present state of development in detectors, electronics and on-line data systems will be presented together with descriptions of applications of such equipment in the laboratory.

Stress gradients in the direction of the surface normal influence the shape of the interplanar spacing “d” vs. sin2ψ (where ψ is the specimen tilt) plot obtained from the surface layers of a specimen.(1-3) If the gradients are caused by the shear stresses σ13, σ23, the “d” vs. sin2ψ plot exhibits “psi-splitting”, that is the “d” values measured at positive ψ tilts are different from the values measured at negative if tilts. (2) If the shear stresses σ13, σ23, are zero, but the normal stress σ33 exists in the layets penetrated by the x-ray beam, “d” vs. sin2ψ, plot exhibits curvature. (3) Various methods have been proposed to obtain the complete stress tensor from split or curved “d” vs. sin2ψ data, and all of these methods require the “unstressed” lattice spacing “d0” for their calculations.

There are several methods for the measurement of retained austenite in steels, which influences mechanical behavior and corrosion resistance of steels. Among them, X-ray diffraction methods using a wide angle goniometer or X-ray stress analyzer are commonly used because the methods are non-destructive, giving useful information about residual stress or lattice strain as well.

Results of an experimental X-ray study on 96 synthetic glasses show that the 2θ positions of glass diffraction maxima have an inverse relation to SiO2 concentration in silicate glasses. This relationship is the basis of a new technique for semiquantitative determinations of SiOa in silicate materials by X-ray diffraction methods. Samples to be examined are fused and the resulting glass scanned from 12 to 40° 2θ using CiiKa radiation. The mean 2θ position of the diffraction maximum is a measure of the SiOs content of the glass. Calibration curves for both weight and molecular percent SiO2 vs. 2θ are presented in this report. The technique requires only small, unweighed amounts of sample for analysis ; it is simple, rapid, and utilizes standard diffraction equipment without modification. Its accuracy, at present, allows SiOa determinations to within ±1 to 4% of the actual concentration.

Two principal mathematical methods are used for quantitative XRFA: fundamental parameter calculations and the evaluation of empirical parameter equations. A comprehensive computer program based upon fundamental parameter equations was introduced in 1976 by D. Laguitton and M. Mantler (LAMA-I) and improved by T. C. Huang in 1979 (LAMA-II). The present paper describes the features of the theoretical background of a computer program using a new type of empirical (alpha*-) parameter equations. It is essentially designed for convenient analysis of compounds including those containing chemical elements, that cannot be directly measured by conventional X-ray spectrometers, such as oxides, nitrides, and others. The program also communicates automatically with LAMA in order to establish theoretical tables of alpha*-coefficients as well as conventional alpha-coefficients.

The 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.

The purpose of this work was to develop accurate calibration standards which were fully characterized in terms of uniformity and concentration using fundamental measuring methods. Three similar sets of vacuum deposits were commercially made, each set containing the single deposits CuS, KCl, CaF2, Cr, Fe, Cu, RbNO3, SrF2, MoO3 , BaF2, and Pb. Thickness variations in each deposit were measured with PIXEA (proton induced x-ray excitation analysis) measurements taken at 6 to 8 positions along the deposit diameters. Relative elemental concentrations on corresponding deposits from each set were measured using multiple XRF intercomparisons. One set of deposits was destructively analyzed at the National Bureau of Standards with isotope dilution thermal ionization mass spectrometry (IDMS) in order to calibrate the remaining sets of vacuum deposits. The calibrated deposits were compared with standards from two commercial sources. For seven elements heavier than chlorine there was an average deviation of 13.5% between the calibrated deposits and the commercial standards. Disagreements as large as 15% were observed between standards from the two commercial suppliers.