中文摘要：

通过对热连轧GH4169合金进行直接时效处理、蠕变性能测试和组织形貌观察,研究了直接时效对热连轧合金蠕变行为的影响。结果表明：直接时效可明显提高热连轧GH4169合金的蠕变抗力,在660℃/700MPa条件下,使合金的蠕变寿命由60h提高到126h,在试验的温度和应力范围内,测定出该合金在蠕变期间的激活能和应力指数分别为Qa=559.2kJ/mol和n=17.6。合金在热连轧期间的变形特征是孪晶和位错在孪晶内的双取向滑移,且有较小的晶粒尺寸;经直接时效后,合金中弥散析出的细小γ″相是有效提高合金蠕变寿命的主要原因。在蠕变期间,合金的变形特征是孪晶及位错在基体中滑移;蠕变后期,在与应力轴垂直的晶界处首先出现微裂纹,随蠕变进行,微裂纹沿晶界扩展并发生沿晶断裂。

英文摘要：

By direct aged treatment,creep properties measurement and microstructure observation,the influences of the direct aged treatment on the creep behaviors of Hot Continuous Rolling GH4169 Superalloy are investigated.Results show that the creep resistance of Hot Continuous Rolling GH4169 Superalloy may be obviously improved by directly aged treatment.Under the applied stress of 700MPa at 660℃,the creep life of the alloy is enhanced to 126h from 60h.In the range of the applied stresses and temperature,the creep activation energy and stress exponent of the alloy during steady state stage are measured to be 559.2kJ/mol and 17.6,respectively.During hot rolling,the deformation features of the alloy are the twinning and the double orientations slipping of the dislocation activated within the twinning regions.And the alloy displays a smaller grain size.After direct aged treatment,the finer（＂phase is dispersedly precipitated in the matrix of the alloy,which is a main reason of enhancing creep life of the alloy.During creep,the deformation features of the alloy are the twinning and dislocation slipping activated in the matrix of the alloy.In the later period of creep,the micro-cracks are appeared in the grain boundaries regions vertical to the applied stress axis,and the micro-cracks are expanded along the boundaries as creep goes on,Which is thought to be the mechanism of the alloy crept up to fracture.