固溶处理的热连轧GH4169合金的组织与蠕变特征

通过对热连轧GH4169合金进行固溶和时效处理、组织形貌观察和蠕变性能测试,研究了固溶和时效处理合金的组织结构和蠕变特征。结果表明,经固溶和时效处理合金由较大尺寸晶粒组成,并具有明显的孪晶特征,且细小γ′、γ″相在晶内弥散析出,可提高合金的蠕变抗力;在实验应力和温度范围内,测得该合金的蠕变激活能为537.8kJ/mol,且对施加应力和温度具有敏感性;在蠕变期间,热连轧GH4169合金的变形特征是位错的单双取向滑移和孪晶变形,随着蠕变进行,裂纹沿晶界萌生和扩展到发生沿晶断裂是该合金的蠕变断裂机制。

Microstructure and Creep Features of Hot Continuous Rolled GH4169 Superalloy after Being Solution Treated

The microstructure and creep features of the solution and aging treated alloy has been investigated.The results show that,after solution and aging treatment,the microstructure of the alloy consists of larger grains with obvious twinning features.Moreover,a great deal of fine γ′ and γ″ phases precipitate in the grains,which can enhance the creep resistance of the alloy.In the ranges of experimental stress and temperature,the creep active energy is about 537.8kJ/mol,and the alloy is sensitive to the applied stress and temperature.During creep,the deformation features of the alloy are dislocation slipping with single or double orientations and twinning deformation.As the creep goes on,the initiation and propagation of the cracks along the grain boundaries lead to intergranular fracture,which is thought to be the fracture mechanism of the alloy.