汽轮机焊接转子接头低周疲劳过程损伤变量的复合分析法  

Combined analysis method for low-cycle fatigue damage variables in the welded joint of steam turbine rotors

作　　者：蔡志鹏[1] 吴健栋[1] 汤之南 张伯奇[1] 潘际銮[1] 刘霞[1,2] 

机构地区：[1]清华大学机械工程系,北京100084 [2]上海汽轮机厂技术发展处,上海200240

出　　处：《清华大学学报（自然科学版）》2014年第2期178-184,共7页Journal of Tsinghua University(Science and Technology)

基　　金：甘肃省有色金属新材料重点实验室开放基金项目(SKL12001)

摘　　要：分析焊接转子接头的低周疲劳损伤过程对转子的安全性评估具有重要的指导意义。该文采用疲劳损伤力学的方法分析NiCrMoV钢汽轮机低压焊接转子1∶1模拟件接头低周疲劳过程。针对损伤变量表征方法中的弹性模量法和应力幅值法应用的局限性,并考虑循环前期循环软化(硬化)造成的材料损伤,提出了适用于循环软化材料或者循环前期出现短暂循环硬化、随后循环软化的材料的低周疲劳全过程损伤变量的分析方法——复合分析法。试验结果表明:在NiCrMoV钢汽轮机低压焊接转子接头的低周疲劳损伤过程分析中,采用复合分析法较弹性模量法和应力幅值法更为合理。Analyses of low cycle fatigue damage to welded joints in turbine rotors are significant to safety assessments. In this paper, fatigue damage mechanics are used to analyze low-cycle fatigue in a 1 ： 1 simulated sample of a NiCrMoV steel low-pressure （LP） steam turbine welded rotor. The elastic modulus method and the stress amplitude method both cannot accurately represent the fatigue damage variable, so this paper presents a combined analysis method, which considers the material damage during cyclic softening （or hardening） in cyclic softening materials or materials with cyclic hardening followed by softening. The results are better than with previous methods for low-cycle fatigue analyses of NiCrMoV steel LP steam turbine welded rotors.

关 键 词：NiCrMoV钢 焊接转子 低周疲劳 损伤变量 

分 类 号：TG457.1[金属学及工艺—焊接]