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研究了TiAl基合金中平衡态和热压力加工状态的α2/γ层片状晶团及其在α+γ两相区加热时显微组织的热稳定性。试验结果表明,由于在层片状晶团内的相邻板条之间存在着一定的位向关系和有序γ相内原子扩散困难,致使新晶粒难以在晶团内形核,板条界面也难以进行迁移,从而阻碍板条向等轴状晶粒转变。所以,TiAl基合金α2/γ层片状晶团在α+γ两相区加热时,表现出高的显微组织热稳定性。从而揭示了热处理细化TiAl基合金的必要条件
The α2 / γ lamellar lumps in the equilibrium and hot-pressed state of TiAl-based alloys were investigated and the thermal stability of the microstructures in the α + γ two-phase region was investigated. The experimental results show that due to the existence of a certain orientation relationship between the adjacent slats in the lamellar crystal lattice and the difficulty of atom diffusion in the ordered γ phase, new crystal grains are difficult to nucleate in the crystal lattice. The interface is also hard to migrate, hindering the slab from transitioning to equiaxed grains. Therefore, Ti-Al-based alloy α2 / γ lamellae are heated in α + γ two-phase zone, showing high thermal stability of the microstructure. Thus revealing the necessary conditions for heat treatment of refined Ti Al-based alloy