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采用反应自生法制备了 ＴｉＣ颗粒增强钛合金基复合材料，研究了复合材料的相组成和微观组 织．在 Ｔｉ－６Ａｌ－２Ｃ合金中存在 Ｔｉ和 ＴｉＣ两种相． ＴｉＣ以树枝状初生 ＴｉＣ和短棒状共晶 ＴｉＣ两种 形态存在，其中共晶 ＴｉＣ主要存在于晶界，特别是三角晶界处 ＴｉＣ晶格常数的计算结果表明 ＴｉＣ的 衍射峰存在一定的偏移，主要是由于存在于 ＴｉＣ中的 Ｃ空位引起晶格畸变。随着 Ａｌ含量的增加，初生 ＴｉＣ由发达粗大的树枝晶变为不发达的树枝晶，当 Ａｌ含量为 ３５％时变为短棒状和薄片状的 ＴｉＣ．基体 组织也相应地由单一的 Ｔｉ基体变为 Ｔｉ和 Ｔｉ３Ａｌ的两相基体以及 Ｔｉ３Ａｌ和 ＴｉＡｌ两相基体．根据相图 分析了组织变化的主要原因．
TiC particles reinforced titanium alloy matrix composites were prepared by reaction spontaneous method. The phase composition and microstructure of the composites were studied. There are two phases of Ti and TiC in Ti-6Al-2C alloy. TiC exists in the form of dendritic primary TiC and short rod eutectic TiC. The eutectic TiC exists mainly in the grain boundaries, especially the lattice constants of TiC at the triangular boundaries show that there is a certain shift in the diffraction peaks of TiC , Mainly due to lattice distortion caused by C vacancy existing in TiC. With the increase of Al content, primary TiC changed from developed coarse dendrites to underdeveloped dendrites. When Al content was 35%, TiC became short rod and flake. The matrix structure is correspondingly changed from a single Ti matrix to a two-phase matrix of Ti and Ti3Al as well as a two-phase matrix of Ti3Al and TiAl. According to the phase diagram analysis of the main reasons for organizational changes.