原位热压TiC/Ti/Al合成Ti_2AlC的研究

Fabrication of Ti_2AlC Material by In-Situ Hot Pressing TiC/Ti/Al Powder Mixtures

以TiC/Ti/Al为原料 ,采用热压工艺在 1 40 0℃原位合成和烧结了含少量第二相Ti3AlC2 的Ti2 AlC材料。通过不同温度和不同热压时间下合成试样的XRD分析探讨了Ti2 AlC的合成过程。结果表明 ,高温下Ti与Al反应生成中间相TiAl金属间化合物 ,然后TiC与TiAl金属间化合物反应生成Ti2 AlC。初期反应非常迅速 ,大部分Ti2 AlC在此阶段生成。反应后期反应物减少 ,速度变慢 ,同时生成少量第二相Ti3AlC2 。不同温度下合成的Ti2 AlC颗粒具有不同的形貌特征。

Ti 2AlC bulk material with a few amounts of seconday phase Ti 3AlC 2 was s ynthesized by in-situ hot pressing TiC/Ti/Al powder mixtures at 1400℃. The synt hesis process of Ti 2AlC was analyzed based on the XRD patterns of samples prepared at different temperatures and different soak ing time by hot pressing.Results show that Ti reacts with Al to form intermediat e phase TiAl at high temperature and then TiAl reacts with TiC forming Ti 2Al C. The reaction speed is very fast at the early stage and most Ti 2AlC appears du rin g this period.At final stage,TiC and TiAl is very few,reaction speed is slow and secondary phase Ti 3AlC 2 comes out.Ti 2AlC particels synthesized at differ ent temperatures have different microstructure.