氢致裂纹中氢压的理论表征及有限元求解方法  

Characterization of hydrogen gas pressure inner hydrogen induced crack cavity using fracture mechanics theory and finite element method

作　　者：付雷[1,2] 单龙 温玉霜 王苹 方洪渊[1] FU Lei;SHAN Long;WEN Yushuang;WANG Ping;FANG Hongyuan(State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150001,China;Xuzhou XCMG Environmental Technology Co.,Ltd.,Xuzhou 221001,China)

机构地区：[1]哈尔滨工业大学先进焊接与连接国家重点实验室,哈尔滨150001 [2]徐州徐工环境技术有限公司,徐州221001

出　　处：《焊接学报》2019年第11期8-12,I0001,共6页Transactions of The China Welding Institution

摘　　要：为了准确表征氢致开裂机理的氢压理论中氢压对裂纹扩展的作用强度,采用断裂力学理论系统地研究了氢压的表征方法及有限元计算的方法.根据氢压的作用方式及断裂力学相关理论,选择以I型裂纹为例,以K因子理论为基础推导了应力强度因子表征氢压作用的公式,包含线弹性模型与弹塑性模型下氢压单独加载与氢压和外载混合加载两种情形下的理论表征方式,分析了有限元方法求解氢压作用表征的几种方法.结果表明,使用J积分表征氢压对裂纹作用强度并不适用,而K因子表征却具有相当高的合理性与准确性,并且位移法比应力法更适宜表征氢压作用.In order to characterize the effect of hydrogen pressure on crack propagation accurately, the characterization method was analyzed using the fracture mechanics theory, then several finite element(FE) methods were used for calculating the hydrogen pressure effect.According to the loading direction of hydrogen pressure, the mode I crack was chosen as an example. Based on the fracture mechanics reasoning, the theoretical formulas for characterizing hydrogen pressure using stress intensity factors(SIF)under the linear elastic model and the elastoplastic model were obtained. The results of FE calculation showed the J integral method is not suitable for the characterization of hydrogen pressure effect on the crack growth. However, SIF had the considerable rationality and accuracy for characterization. In addition, the displacement method is more suitable than the stress method for calculating the SIF of hydrogen pressure.

关 键 词：氢压理论 断裂力学 有限元计算 线弹性模型 弹塑性模型 

分 类 号：TG404[金属学及工艺—焊接]