超高强铝合金盘型件开裂原因分析  

Causes Analysis of Cracking on Ultra-high Strength Aluminum Alloy Disc

作　　者：李昂[1,2,3] 张毅 陈开媛[1,2,3] 吴福 高蔚 LI Ang;ZHANG Yi;CHEN Kai-yuan;WU Fu;GAO Wei(Institute of Physical and Chemical Engineering of Nuclear Industry,Tianjin 300180,China;Innovation Center of Nuclear Materials for National Defense Industry,Tianjin 300180,China;Science and Technology on Particle Transport and Separation Laboratory,Tianjin 300180,China)

机构地区：[1]核工业理化工程研究院,天津300180 [2]国防科技工业核材料技术创新中心,天津300180 [3]粒子输运与富集技术重点实验室,天津300180

出　　处：《失效分析与预防》2023年第6期394-399,共6页Failure Analysis and Prevention

基　　金：粒子输运与富集技术重点实验室基金项目(SYSJJ-22410);中核集团青年英才计划菁英项目(CNNC2019YTEP-IPCE01)。

摘　　要：超高强铝合金盘型件在运行1.5月后盘体边缘发生开裂。通过裂纹宏微观形貌观察、化学成分检验、局部力学性能测试、服役应力有限元模拟、显微组织分析等手段,确定盘型件的开裂原因。结果表明:裂纹附近区域化学元素含量满足技术规范要求;裂纹局部径向拉伸性能满足零件服役需求,裂纹附近区域的金相组织未见明显异常,超高强铝合金盘型件的热处理工艺满足材料技术条件要求;盘型件断口的断裂特征为沿晶断裂;起裂部位靠近盘体内表面;O、Fe夹杂物的聚集是造成运行条件下盘体裂纹萌生并扩展的主要原因。An ultra-high strength aluminum alloy disc cracked near the edge after service for 1.5 months.The cracking cause of the disc was investigated by micro and macro observation,chemical composition analysis,local mechanical properties testing,finite element simulation(FEM)of in-service stress,and metallographic examination.The results indicate that the chemical composition near the crack meets the requirements of corresponding technical specifications,the local radial tensile properties near the crack meets the service requirements of the disc,and no obvious abnormality was found in the microstructure near the crack.Moreover,the heat treatment process of the disc meets the service requirements of the material.The fracture surface of the disc shows intergranular fracture feature.The cracking source is near the inner surface of the disc.The aggregation of oxides and ferric inclusions at the cracking source region is the main reason for the initiation and extension of the crack.

关 键 词：超高强铝合金 环向裂纹 盘型件 夹杂物 沿晶断裂特征 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG115.2[金属学及工艺—金属材料]