基于扩散-内聚力耦合模型的316L不锈钢溶解氧环境下应力腐蚀开裂速率仿真分析  

NUMERICAL SIMULATION ON STRESS CORROSION CRACK GROWTH RATE OF 316L STAINLESS STEEL IN DISSOLVED OXYGEN ENVIRONMENT BASED ON A COUPLED DIFFUSION-COHESION MODEL

作　　者：巴思博 凌玲[1] 张骏杰 王学林[1] BA SiBo;LING Ling;ZHANG JunJie;WANG XueLin(School of Mechanical Science&Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]华中科技大学机械科学与工程学院,武汉430074

出　　处：《机械强度》2024年第6期1441-1448,共8页Journal of Mechanical Strength

基　　金：国家自然科学基金项目(51875219)资助。

摘　　要：高温水环境下溶解氧是影响奥氏体不锈钢应力腐蚀开裂的主要环境参数之一。基于应力腐蚀的滑移-溶解理论,建立了一种氧扩散与内聚力耦合的应力腐蚀裂纹模拟模型。采用内聚力有限元数值方法模拟了在325℃高温水溶解氧环境下316L奥氏体不锈钢的应力腐蚀开裂行为,分析了溶解氧含量与加工硬化对裂纹扩展速率(Crack Growth Rate,CGR)的影响。结果表明,通过标定的模型参数,建立的模型可以预测不同溶解氧含量下材料应力腐蚀裂纹扩展速率,计算结果与文献中的实验测量结果一致。在模拟的高温水环境和应力强度因子条件下,316L不锈钢应力腐蚀裂纹扩展速率与屈服强度关系可表示为CGR∝σ_(y)^(2.028)。Dissolved oxygen is one of the main environmental parameter affecting of stress corrosion cracking of austenitic stainless steel in high temperature water environment.Based on the slip-dissolution of stress corrosion theory,a coupled diffusion and cohesion model was built for simulating stress corrosion crack.The stress corrosion cracking behavior of 316L austenitic stainless steel in high temperature water of 325℃ with dissolved oxygen was simulated by finite element analysis using cohesive element.The effects of dissolved oxygen content and cold working on crack growth rate(CGR)were analyzed.The results indicate that,by appropriately calibrating the model parameters,the built model can predict the CGR of stress corrosion cracking under different dissolved oxygen contents,showing that the calculated CGR agrees well with the experimental results reported in the literature.Furthermore,the relationship between the stress corrosion crack growth rate and the yield strength of 316L stainless steel can be fitted as CGR∝σ_(y)^(2.028) in the simulated high temperature water and stress intensity factor conditions.

关 键 词：有限元分析 应力腐蚀 内聚力模型 溶解氧 

分 类 号：TG174[金属学及工艺—金属表面处理]