Structure features of the composite materials Inconel 625/TiC, produced by LMD method

Abstract

In this paper, the metal composite material Inconel 625/TiC with 20 % carbide content produced by laser metal deposition (LMD) method was investigated. The initial powders were in three various states: they were fed from single flasks; they were previously mixed in a gravitational mixer or in a planetary ball mill. It was shown that only composites obtained from the powders previously mixed in a planetary ball mill had no cracks. At usage the powder in another states, grown composites had magistal cracks. When cracks did not arise, the carbide particles TiC had initial spherical shape and initial composition. In those cases when cracks appeared, the carbides have dendritic shape, and their composition are changed. Investigation of the powder materials showed that during mixing the individual particles of the Inconel powder are covered with layer of titanium carbide. As a result, the thermophysical properties of Inconel powder are changed, and an energy required for recrystallization of the Inconel powder is increased.