Si和Al对机械合金化合成Ti3SiC2的影响

采用3Ti／Si／2C单质粉体为原料，进行机械合金化，以合成Ti3SiC2粉体。研究了Al和过量Si对机械合金化合成Ti3SiC2的影响。研究结果表明，机械合金化单质混合粉体，会诱发自蔓延反应。反应后产生大量坚硬的颗粒状产物。机械合金化3Ti／Si／2C粉体，会产生组成相为TiC、Ti3SiC2、TiSi2和Ti5Si3的粉体与颗粒产物。添过量Si并不会促进机械合金化反应合成Ti3SiC2。添适量Al可消除硅化物，明显促进反应合成Ti3SiC2。采用3Ti／Si／2C／0．15Al粉体作原料时，颗粒产物中Ti3SiC2含量最高，为92．8wt％；而采用3Ti／Si／2C／0．20Al粉体作原料时，粉体产物中Ti3SiC2含量最高，为61．9wt％。

Effect ofSi and AI on reaction synthesis of Ti3SiC2 by mechanical alloying

3Ti/Si/2C elemental powders were used as the starting materials for the synthesis of Ti3SiC2 powders by mechanical all- oying. Effect of Si and Al element on the reaction synthesis of Ti3SiC2 was investigated. The result shows that mechanical alloying of3Ti/Si/2C powders may induce self-propagation reaction. After reaction, amounts ofrigor granules were produced. Thepowders and granules product contained TiC, Ti3SiC2, TiSi2 and Ti3Si3 were synthesized by mechanical alloying of 3TilSi/2C powders. Excessive Si has no effect on the synthesis of Ti3SiC： by MA. Addition of Al may remove silicide, which obviously promote the synthesis of Ti3SiC2 When the starting materials was 3Ti/Si/2C/0.15Al powders, Ti3SiC2 content of the mechanically alloyed granule products reached the highest value of 92.8wt%. When the raw materials was 3Ti/Si/2C/0.2Al powders, Ti3SiC2 content of the powder products reached the highest value of 61.9wt%.