等温变形对γ-TiAl合金微观组织的影响

通过等温压缩特性及微观组织演变研究，提出了有效的γ-TiAl基合金晶粒细化方法。研究发现，如果γ-TiAl合金锭具有一定的细晶组织便可以在(α2 γ)2相区完成等温变形而不产生裂纹。动态再结晶和静态球化数量的增加是提高γ-TiAl合金变形能力的主要原因。将等温变形的模拟锻件在不同相区进行热处理获得了具有细小尺寸的3种(全片层、近片层和双态)组织。

Effect ofMicrostructure on Isothermal Deformation of

An effective method for grain refining of γ-TiAl alloy was put forward based on the study results of compression behavior and microstructure evolution during isothermal deformation. It was found that the isothermal deformation of γ-TiAl alloy could be performed successfully in the (α2+γ)-phase field if the ingot had a fined microstructure. The workability of γ-TiAl alloy was improved due to the increase of dynamic recrystallization and static globularization. Three kinds of fine microstructures (fully lamellar, near lamellar and duplex) with small sizes were obtained respectively in the as-forged component through post heat-treatment conducted in different phase field.