采用水冷铜坩埚真空感应熔炼(ISM)技术制备β型TiAl合金Ti-45Al-2Nb-1.5V-1Mo-0.3Y(摩尔分数，%)及其复合材料Ti-45Al-2Nb-1.5V-1Mo-0.3Y(摩尔分数，%)＋3%TiB2(体积分数)两种材料，并对TiAl合金及其复合材料的显微组织、力学性能和抗氧化性能进行研究。结果表明：加入TiB2后，TiAl合金中的晶粒尺寸和层片间距都得到细化，显微硬度、室温和高温抗拉强度提高，但室温伸长率略有下降，高温时复合材料表现出良好的塑性；800℃循环氧化100 h后，TiAl合金和复合材料氧化表面均保持完整，未产生剥落；加入TiB2后，导致两种材料表面氧化物的生长形态发生变化，但两种材料的氧化增量和氧化层厚度相近，因此，TiB2对氧化物的生长形态有影响，但对抗氧化性能影响不大。%TiAl-based alloy Ti-45Al-2Nb-1.5V-1Mo-0.3Y (mole fraction,%) and composites Ti-45Al-2Nb-1.5V-1Mo-0.3Y (mole fraction, %)+3%TiB2 (volume fraction) were prepared by induction skull melting (ISM). The microstructure, mechanical properties and oxidation resistance were studied. The results show that the composites exhibit much finer lamellar colony size and lamellar spacing compared with matrix. The micro-hardness and tensile fracture strength are improved at room temperature and 800℃, while the tensile elongation decreases at room temperature. The composites show good plastics at 800℃. After oxidation in air at 800℃for 100 h, the oxidation surfaces of matrix and composites show good quality with no micro-cracks observed. The growth morphologies of matrix oxidation surface change compared with those of composites. But the mass gain and thickness of oxide scale of composites are almost the same as those of matrix. So, TiB2 has some influence on the growth morphologies of oxide scale, but nearly has no influence on the oxidation resistance.
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