采用真空感应熔炼炉将成分为Ti-6.55Al-3.41Mo-1.77Zr(质量分数)的α+β钛合金在石墨模具中浇铸成棒材。铸态棒材在700°C下热锻后，通过两种不同的热处理后，分别得到细小和粗大的层片状结构。结果表明：铸态组织的晶粒尺寸约为660µm，而锻造后样品具有细小的晶粒尺寸，约为50µm。在1050°C热处理后的α+β钛合金具有细小的层片状结构，得到最佳的硬度、拉伸性能和耐磨性。在800°C热处理后的α+β钛合金具有粗大的层片状结构，具有最大的抗压强度。具有细小层片状结构的热处理态α+β钛合金的磨损率较小，而铸态α+β钛合金由于具有粗大和不均匀的微观组织，因此磨损率较大。%α+βtitanium alloy with a composition of Ti-6.55Al-3.41Mo-1.77Zr (mass fraction,%) was cast into bars in a graphite mould using vacuum induction skull melting furnace (ISM). The cast bars were hot swaged at 700 °C and then heat treated by two different regimes which resulted in fine and coarse lamella structures, respectively. The grain size of the as-cast structure was estimated to be 660 µm and the swaged samples obtained a very fine grain size in the range of 50 µm. The overall best combination of hardness, tensile properties, and wear resistance of theα+βtitanium alloy was achieved by heat treating the samples at 1050 °C for getting fine lamellar structure. The maximum compression strength was reported for the heat treated samples at 800 °C with coarse lamella structure. The minimum wear rate was reported for the heat treated samples with fine lamellar structure and the maximum wear rate was obtained for as-cast samples due to its coarse and heterogeneity microstructure.
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