22NiMoCr3-7钢椭圆裂纹体断裂预测  

Fracture predicting for semi-elliptic surface crack on 22NiMoCr3-7 steel plate

作　　者：王钟羡[1] 张瑞峰[1] 吴春笃[2] 

机构地区：[1]江苏大学理学院,江苏镇江212013 [2]扬州环境资源职业技术学院,江苏扬州225127

出　　处：《江苏大学学报（自然科学版）》2012年第3期354-358,共5页Journal of Jiangsu University：Natural Science Edition

基　　金：国家"863"计划项目(2008AA100905)

摘　　要：采用ABAQUS有限元分析软件对核压力容器用22NiMoCr3-7钢椭圆裂纹体进行弹塑性数值计算,用J-A2双参数描述韧-脆转变温度区椭圆裂纹前沿的应力场,根据RKR断裂准则预测椭圆裂纹扩展的起始点和材料韧-脆转变参考温度.结果表明:载荷一定时,随着温度的上升,J积分和约束参数A2也相应提高,温度对J积分的影响比对约束参数A2的影响要大;浅椭圆裂纹的最大J积分值出现在最深点处,而半圆裂纹则出现在表面点附近;根据RKR准则和J-A2三项解建立断裂预测公式,可以将标准三点弯曲试样的断裂韧性测试数据转移应用到带表面裂纹构件的断裂评估,为解决工程实际问题提供一种实用方法.Based on three-dimensional elastic-plastic finite element analysis,the semi-elliptic surface cracks on 22NiMoCr3-7 pressure vessel steel plate were numerically calculated by ABAQUS software.The crack driving force of J and the crack tip constraint parameter of A2 were calculated from FEA results in the ductile-brittle transition range to describe the near crack tip stress fields.Based on J-A2 and RKR fracture theories,the ductile-brittle transition reference temperature of T0 and the crack propagation initiating spots were predicted.The results show that the maximum of J is at the deepest crack front of elliptic crack for the shallow semi-elliptic surface cracks,while that is near the crack edge for the semi-circle surface cracks.J and A2 are increased when temperature raises.The temperature effect on crack driving force of J is greater than that on crack tip constraint parameter of A2.Based on J-A2 approach and RKR fracture model,the predicting formula can well transfer the fracture toughness parameter from standard three-point bend samples to cracked structures for structural integrity assessment.

关 键 词：22NiMoCr3-7钢 椭圆裂纹 断裂韧度 断裂约束 韧-脆转变区 

分 类 号：O346.1[理学—固体力学]