TiB_2－xAl复合材料的结构形成分析

PROPOSAL OF STRUCTURE FORMATIONIN SELFPROPAGATING HIGH TEMPERATURE SYNTHESIS OF TiB_2-xAl COMPOSITES

研究了Ｔｉ和Ｂ颗粒尺寸的变化对自蔓延高温合成（ＳＨＳ）ＴｉＢ_２—ｘＡｌ金属基复合材料的燃烧温度和燃烧波速度的影响。结果表明，Ａｌ颗粒不直接参与化学反应，其尺寸变化对ＳＨＳ过程的影响要小得多，但是反应过程中形成的熔融Ａｌ能阻止ＴｉＢ_２晶粒的长大，因而可以控制ＳＨＳ产物的结构。通过燃烧波峰淬熄（ＣＦＱ）法，对该复合材料的ＳＨＳ过程结构形成机理进行了分析。

Effect of of Ti or B particle size on the combustion temperature and propa gating rate in the self propagating high temperature synthesis(SHS) process of TiB_2-xAl composites has been investigated.The size change of Al particles,which does not directly enter into the chemical reaction as Ti and B,may be much less influential to the SHS process.But the molten Al, formed during reaction, may retard the growth of TiB_2grains. Thus, the structure of SHS product can be controlled.By means of combustion front quenching (CFQ) with copper wedge, the structure formation of TiB_2-xAl composites in the SHS process was discussed