A Ti-48Al-2Cr-2Nb alloy was prepared by electron beam smelting. The effect of solution parameters on the microstructures, constituent phases and hardness was studied. The results show that impurities in the alloy could be significantly removed after electron beam smelting. The content of O and N in the ingot after smelting is about 93.25 and 25.75 ppmw, respectively. The average grain size of the ingot is 250 μm, and the lamellar spacing varies from 40 to 200 nm. As the solution temperature increases, the microstructure is coarsened obviously, accompanied with the increase in lamellar spacing. The lamellar spacing, the grain size and the microhardness of the alloy increase gradually as the solution time increases. When the alloy is solution treated at 1320 °C for 30 min, a uniform microstructure can be acquired, whose grain size is about 500 μm with an average lamellar spacing of 200 nm. The microhardness of the alloy after optimized heat treatment is 400HV.

采用电子束熔炼制备Ti-48Al-2Cr-2Nb合金。研究了溶液参数对显微组织、组成相和硬度的影响。结果表明，电子束熔炼后合金中的杂质得到明显去除。熔炼后铸锭中O和N的含量分别约为93.25和25.75 ppmw。铸锭的平均晶粒尺寸为 250 μm，层状间距从 40 到 200 nm 不等。随着固溶温度的升高，显微组织明显粗化，层间距增大。随着固溶时间的增加，合金的层间距、晶粒尺寸和显微硬度逐渐增加。当合金在 1320°C 下进行 30 分钟的固溶处理时，可以获得均匀的显微组织，其晶粒尺寸约为 500 μm，平均层间距为 200 nm。优化热处理后合金的显微硬度为400HV。