Distribution of Substitutional Alloying Elements and Interstitial Impurities in In Situ Multicomponent Composites Based on the Nb-Si System

摘要

The distribution of substitution alloying elements in the structure of hexagonal silicide Nb~(5)Si~(3)of the γ-modification, which serves as a reinforcing phase of the composite, and in the Nb solid solution matrix of a high-temperature natural composite based on Nb–Si is studied. Studies were carried out on samples in a cast state and after homogenizing thermal treatment. A structural model of the γ-modification of silicide Nb~(5)Si~(3)is constructed. On the basis of the crystal-chemical analysis of the structure of hexagonal silicide, possible causes of phase instability of the composite after thermal treatment are revealed.