Structure of the metal matrix Mo-based alloy produced by the EBM method

Abstract

We perform structural investigations of a molybdenum-based cermet material obtained by the method of selective electron-beam melting. The initial material is an alloy of the Mo–Si–B system alloyed with a reinforcing component in the form of an Al₂O₃–Y₂O₃–ZrO₂ oxide composition. It is shown that, in the process of selective electron-beam melting of spheroidized cermet particles of the alloy of Mo–Si–B system in the optimal technological mode of synthesis, we observe melting both of the molybdenum matrix of the alloy and of the reinforcing particles contained in the original granules. As a result, in the course of crystallization of the melt with formation of a cellular structure on the boundaries of cells, we observe the appearance of finely divided oxide particles 1–5 μm in size, which are also composite particles. On the boundaries of cells and inside oxide inclusions, we reveal the elevated content of silicon as compared to that in the body of cells, which enables us to conclude that the processes of diffusion of this element occur in the analyzed material. At the same time, in the vicinity of the contour of samples of synthesized material, we detect the formation of a structure, which inherits, to a certain extent, the structure of the initial spheroidized granules.