X70钢焊接接头不同区域低温CTOD特征值分布规律  

Distributions of the Low-Temperature CTOD Values for the Different Zones of X70 Welded Joint

作　　者：郭亚杰[1] 王宇晴 曹志强 蔡和平[2] 刘硕[3] GUO Yajie1, WANG Yuqing1, CAO Zhiqiang1, CAI Heping2, LIU Shuo3(1. School of Materials Science and Engineering, Chang＇an University, Xi＇an 710064, China; 2. State Key Laboratory for Mechanical Behavior of Materials, Xi＇an Jiaotong University, Xi＇an 710049, China; 3. Baoshan Iron ＆ Steel Co., Ltd., Shanghai 201900, Chin)

机构地区：[1]长安大学材料科学与工程学院,陕西西安710064 [2]西安交通大学金属材料强度国家重点实验室,陕西西安710049 [3]宝山钢铁股份有限公司,上海201900

出　　处：《铸造技术》2018年第4期854-857,共4页Foundry Technology

基　　金：国家自然科学基金青年项目(51401034);陕西省重点研发计划项目(2017GY-033);长安大学创新创业训练项目(201610710083)

摘　　要：高强度钢焊接接头焊缝中心区、熔合线区和热影响区的组织结构与元素分布的不同造成这3个区域的裂纹尖端张开位移(CTOD)及其离散性存在差异,给焊接接头可靠性评估带来挑战。对X70级高强度钢电弧焊焊接接头的上述3个区域分别进行了低温CTOD特征值测试,并对各区域CTOD特征值的分布规律进行了统计研究。结果表明,焊缝中心区的CTOD特征值离散性较小,符合对数正态函数分布规律;熔合线区域的CTOD特征值离散性最大,同样符合对数正态分布;热影响区的CTOD特征值均值最大,但更符合正态分布函数规律。Owing to the different structure and element distribution among the welding center zone, fusion-line zone and heat-affected zones in the welded joint of high strength steel, the difference of the crack tip opening displacement（CTOD）with respect to these zones brings out a challenge to evaluate the reliability of the welded joints. In the present study,low-temperature CTOD experiments of the X70 high strength steel joints were conducted. Moreover, distributing fitting testing and statistical distribution analysis was performed to investigate the CTOD distribution of the different zones. The results show that the CTOD values of the welding centre zone exhibit lighter discreteness and conformed to the log-normal function distribution. The values of the fusion-line zone show the same distribution tendency, regardless of the maximal discreteness degree among the three zones. The CTOD values of the heat-affected zone show the maximum mean, agreeing well with the normal distribution function.

关 键 词：焊接接头 CTOD 离散性分布 拟合检验 

分 类 号：TG407[金属学及工艺—焊接]