作　　者： ; ; ; ; ;

机构地区： 沈阳工业大学材料科学与工程学院

出　　处： 《材料工程》 2012年第10期1-7,共7页

摘　　要： 通过对不同方式冷却的热连轧GH4169合金进行直接时效处理、蠕变性能测试和组织形貌观察,研究了冷却方式对热连轧GH4169合金的组织结构与蠕变行为的影响。结果表明:"水冷"HCR-GH4169合金经直接时效后,其组织由细小晶粒组成,大量细小γ′,γ″相在晶内弥散析出,可提高合金蠕变抗力,而"空冷"热连轧合金晶粒尺寸较大,且在基体中析出的γ′,γ″两相的数量明显减少;在实验条件下,"水冷"热连轧合金经直接时效后具有较好的蠕变抗力和较长的蠕变寿命;热连轧及直接时效合金在蠕变期间的变形机制是位错在基体中发生单、双取向滑移和孪晶变形,在蠕变后期,裂纹在晶界处萌生和扩展,并发生沿晶断裂是合金的蠕变断裂机制。 By means of direct aging treatment,creep properties measurement and microstructure observation,the influence of cooling methods on microstructure and creep behaviors of HCR-GH4169 alloy has been investigated.Results show that,after directly aged treated,the ＂water cooling＂ HCR-GH4169 alloy possesses the fine grains in size,and significant amount of the γ′,γ″ phases are dispersedly precipitated within the grain,which can enhance the creep resistance of the alloy.However,the bigger grain in size is displayed within the ＂air cooling＂ HCR-GH4169 alloy in which the amount of γ′,γ″ phases decrease.Under the experimental condition,the ＂water cooling＂ HCR-GH4169 alloy possesses the longer creep lifetime.The deformation mechanisms of the direct aged HCR-GH4169 alloy are the twinning deformation and single or double orientations slipping of dislocations activated in the matrix.In the later stage of creep,the initiation and propagation of the cracks along the grain boundaries occur to promote the intergranular fracture of the alloy,which is thought to be the fracture mechanism of the HCR-GH4169 alloy during creep.

关 键 词： 热连轧 合金 冷却方式 组织结构 蠕变 变形机制

领　　域： [金属学及工艺] [一般工业技术] [金属学及工艺]