C-276合金650℃下持久抗力的显微分析  

Microstructure Analysis of Stress Rupture Performance of Hastelloy C-276 Alloy at 650℃

作　　者：马雁[1] 陆道纲[1] 毛雪平[1] 张立殷[1] 蔡军[1] 

机构地区：[1]华北电力大学,北京102206

出　　处：《稀有金属材料与工程》2010年第9期1571-1574,共4页Rare Metal Materials and Engineering

基　　金：国家重点基础研究发展计划("973"计划)(2007CB209803)项目;长江学者和创新团队发展计划(IRT0720);华北电力大学留学回国人员科研基金

摘　　要：利用SEM和TEM,对固溶强化合金Hastelloy C-276的初始组织和在650℃、不同拉应力下持久断裂试样进行显微组织分析。结果表明:试样的断口以典型的韧窝形貌为主,局部有少许晶间断裂现象,显示出C-276合金具有良好的高温韧性。在C-276合金的初始组织中,有退火孪晶和大量位错存在;在经受高应力拉伸过程中,晶体内产生大量形变孪晶;同时,发现在晶界和晶内有细小弥散的析出物。因此,C-276合金在650℃下优越的高温持久抗力是固溶强化、沉淀强化以及可能的孪晶强化综合作用的结果。The microstructure of solid solution strengthened Hastelloy C-276 alloys before and after ruptured at 650 oC under different tensile stresses was studied by SEM and TEM.The results show that the fracture surface displays typical dimple morphology,with a few intergranular fractures.It can be concluded that the C-276 alloy has very good high-temperature toughness.A few annealing twins and plenty of dislocations exist in the initial microstructure of C-276 alloy.And after persistent tensile experiments,a large number of deformation twins are formed in C-276 crystals.Moreover,many fine and dispersive precipitations are also formed in the grain boundary and intragranular.Therefore,a good high temperature stress rupture performance of the Hastelloy C-276 alloy arises from co-effects of solid solution-strengthening,precipitation-strengthening and possible deformation twin-strengthening.

关 键 词：固溶强化合金 高温持久 抗力 显微分析 Performance Stress Rupture Analysis 初始组织 显微组织分析 综合作用 形变孪晶 退火孪晶 试样 孪晶强化 拉伸过程 结果 断裂现象 持久断裂 沉淀强化 析出物 

分 类 号：TG146.15[一般工业技术—材料科学与工程]