Al含量对TiC自蔓延高温合成过程的影响

EFFECT OF Al CONTENT UPON SHS EXPLOSION PROCESS FOR TiC

对不同Ａｌ含量ＴｉＣ体系的燃烧合成进行了研究，结果表明：Ａｌ的掺入使得ＴｉＣ的合成反应可以在较低温度下引发；Ａｌ首先与Ｔｉ反应形成Ｔｉ与Ａｌ的化合物，放出热量；随后促使Ｔｉ与Ｃ的放热反应发生，合成ＴｉＣ时放出的高热使Ｔｉ与Ａｌ的化合物在高温下与Ｃ反应形成ＴｉＣ和Ａｌ，使得合成产物中只有ＴｉＣ和Ａｌ两相。体系中Ａｌ含量的增加会使合成ＴｉＣ颗粒尺寸变小。

The effects of aluminium content in the TiCAl systems upon the thermal explosion process,phase composition and microstructure of the reaction products were studied,and the mechanism of reactive synthesis is discussed.Results show that the explosive reaction of the TiCAl system proceeds in such a way that aluminium reacts initially with titanium to form titanium aluminide compounds with heat evolution during the reaction,and then the reaction between titanium and carbon was accelerated.Titanium aluminide compounds react with carbon to form TiC and Al at high temperature under the heat dissipated in the TiC reaction.The grain size of TiC decreases with the increase of aluminium content in TiCAl system.