Effect of Carbon and Aluminum Content on the Structurization of the Al-Ti-C Powder Master Alloy during Reaction Synthesis

Abstract

The paper presents results of electron microprobe, X-ray diffraction, and differential thermal analyses of master alloys produced by reaction synthesis of Al—Ti—C powder mix¬tures of various compositions. It is shown that heating of all stating mixtures leads to in situ precipitation of titanium carbide particles and complex titanium-aluminum carbides. Spheri¬cal titanium carbide particles are the predominant strengthening phase in samples with high carbon content (10-13%) and disordered elongated acicular grains of complex titanium-aluminum carbides in samples with minimum carbon content (6%) and relatively high aluminum content (40%). It is established that 45 wt.% Al-11 wt.% C-44 wt.% Ti master alloy having practically equal aluminum and titanium contents is characterized by the finest strengthening phase particles after thermal synthesis.