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采用单辊旋淬快速凝固设备制备了Ti-48Al-4Cr(at%)薄带,并在真空封装后进行热处理,研究了热处理对快速凝固Ti-48Al-4Cr合金组织演变的影响。结果表明,快速凝固Ti-48Al-4Cr合金凝固基体为等轴的γ相,基体中含有少量的B2相、α_2相颗粒和片层组织;经723℃保温1 h空冷后,亚稳的α_2相颗粒失稳,但片层组织仍然比较稳定;热处理温度升高至932℃时,片层组织中的杆状α_2相开始按照“瑞利”分解失稳,分解成大量短杆状或者颗粒状的α_2相;在995℃保温1 h以后,基体中已较难发现片层组织存在,但存在着排列方向相同的棒状α_2相,同时在等轴γ相晶界处发现了数量较多的颗粒状B2相。
Ti-48Al-4Cr (at%) thin strip was prepared by single-roll rapid solidification equipment and was heat-treated in vacuum envelope to study the effect of heat treatment on microstructure evolution of rapidly solidified Ti-48Al-4Cr alloy. The results show that the solidified matrix of the rapidly solidified Ti-48Al-4Cr alloy is an equiaxed γ phase with a small amount of B2 phase, α_2 phase particles and lamellar structure. After air-cooling at 723 ℃ for 1 h, the metastable α_2 phase But the lamellar structure is still stable. When the heat treatment temperature is raised to 932 ℃, the rod-like α_2 phase in the lamellar structure begins to decompose and lose its stability in “Rayleigh” Like α_2 phase. After heated at 995 ℃ for 1 h, the lamellar structure was found to be more difficult to be found in the matrix, but there was a rod-like α_2 phase with the same orientation. At the same time, a large number of Granular B2 phase.