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利用螺旋选晶法制备了镍基单晶合金,研究了热处理过程中合金的组织演变。结果表明:合金的铸态组织由枝晶组成,W偏析于枝晶干,Ti、Cr、Mo和Ta偏析于枝晶间,固溶处理可以消除铸态组织中的枝晶,减小成分偏析,固溶温度越高,粗大的γ’和γ/γ’共晶溶解的越完全。时效处理过程中,大尺寸的γ’发生粗化,小尺寸的γ’逐渐消失,时效温度越高,γ’粗化得越严重。热处理促进合金元素在γ和γ’中的均匀分布,减小了合金的错配度。
Nickel-based single crystal alloys were prepared by spiral pick-up and the microstructure evolution of the alloy during heat treatment was investigated. The results show that the as-cast microstructure of the alloy is composed of dendrite, W segregated on the dendrites, and Ti, Cr, Mo and Ta are segregated between the dendrites. The solution treatment can eliminate the dendrite in the as-cast microstructure and reduce the composition segregation, The higher the solution temperature, the more complete dissolution of coarse γ ’and γ / γ’ eutectic. During the aging treatment, large-size γ ’coarsening and small-size γ’ gradually disappear. The higher the aging temperature, the more severe the γ ’coarsening. Heat treatment promotes the uniform distribution of alloying elements in γ and γ ’, reducing the mismatch of the alloy.