T92/HR3C异种钢焊接接头高温拉伸变形及断裂行为  

Tensile plastic deformation and fracture behavior of T92/HR3C dissimilar welded joints at high temperatures

作　　者：宋有明[1] 陈国宏[2] 余新海 刘俊建[2] 王家庆[2] 化建 张涛[2] 张建华[1] 汤文明[1] 

机构地区：[1]合肥工业大学材料科学与工程学院,安徽合肥230009 [2]安徽省电力科学研究院材料所,安徽合肥230601 [3]合肥津利能源科技发展有限公司,安徽合肥230601

出　　处：《材料热处理学报》2012年第2期72-78,共7页Transactions of Materials and Heat Treatment

基　　金：安徽省电力科学研究院技术开发基金(2009咨-JS-03);安徽省高校自然科学研究重点项目(KJ2011A221)

摘　　要：采用500℃和625℃拉伸试验,研究T92/HR3C异种钢管接头的高温变形及其断裂行为。结果表明,在高温拉伸过程中,焊缝、T92侧热影响区(HAZ)及母材(不包含颈缩段)均未发生明显的塑性变形及组织结构的变化,而HR3C侧母材晶粒明显被拉长,HR3C侧HAZ的拉伸变形不明显。HR3C母材塑性变形量随温度升高而明显降低,孪晶回复越少。高温拉伸断口位于T92侧HAZ的细晶区(FGHAZ),呈正断加剪切断的混合断裂方式,均与室温状态下该焊接接头的拉伸变形及断裂行为不同。应力三轴度理论可很好地解释该接头高温短时拉伸变形及断裂特征。Short-term tensile tests of T92/HR3C dissimilar weldedJoints were carried out at 500 ℃ and 625 ℃ to study plastic deformation and fracture behavior of the joints at high temperature.The results show that there are no observable plastic deformation and structural evolution at the welding seam,the heat affected zone（HAZ） of T92,T92 base metal and the HAZ of HR3C steel during the high-temperature tensile tests,except the necking section of the specimens.However,grains of the HR3C base metal are obviously elongated.Plastic deformation of the HR3C base metal decreases with increasing the testing temperature with less twin recovery.The high-temperature tensile fracture of the joints is located at the fine-grained heat affected zone（FGHAZ） closed to the T92 base metal,and a mixed fracture mode under normal stress and shear stress was present,which is different from those of the joints during room temperature tensile tests.The stress triaxiality theory was successfully applied to explain the plastic deformation and facture behavior of the joints during the short-term tensile tests at high temperature.

关 键 词：T92/HR3C异种钢焊接接头 高温拉伸 塑性变形 断裂行为 应力三轴度 

分 类 号：TG142.4[一般工业技术—材料科学与工程] TG407[金属学及工艺—金属材料]