Quantitative Determination of Phase Content of Silicon Nitride by X-Ray Diffraction Analysis.

摘要

Quantitative phase analysis of mixtures of polycrystalline materials is often difficult because of the number of variables that are involved in determining the relative amounts of each phase. Among the important variables are absorption coefficients,structure factors,particle size,and identification and resolution of diffraction peaks. Phases of interest that commonly occur in silicon nitride ceramics are alpha-Si3N4,beta-Si3N4,and unreacted Si. The purpose of this investigation was to establish a simple and reproducible technique for the determination of the phase content of silicon nitride. Of particular concern was the minimization of error due to preferred orientation effects. The general approach involved calculation of the relative intensities of selected diffraction peaks,correction of these to minimize preferred orientation,effects,and comparison of the theoretical results with those obtained from analysis of a standard.