X80管线钢焊接热模拟热影响区疲劳裂纹扩展行为的分析及预测  

Analysis and forecast of fatigue crack propagation behavior in HAZ of X80 pipeline steel by welding thermal simulation

作　　者：徐鹏飞[1] 赵作鹏 程红霞 肖福仁[2] Xu Pengfei;Zhao Zuopeng;Cheng Hongxia;Xiao Furen(Institute of Marine Engineering Equipment and Underwater Technology,Hohai University,Nanjing Jiangsu 210098,China;Key Lab of Metastable Materials Science and Technology and College of Materials Science and Engineering,Yanshan University,Qinhuangdao Hebei 066004,China)

机构地区：[1]河海大学海工装备与水下技术研究所,江苏南京210098 [2]燕山大学亚稳材料制备技术与科学国家重点实验室,河北秦皇岛066004

出　　处：《金属热处理》2020年第12期184-188,共5页Heat Treatment of Metals

基　　金：国家自然科学基金(51171162)

摘　　要：通过焊接热模拟方法对X80双相管线钢不同焊接热影响区疲劳裂纹扩展行为进行了研究,并分析实际焊接试样与焊接热模拟试样的热影响区疲劳裂纹扩展行为的差异,讨论了焊接热模拟技术应用于疲劳裂纹扩展寿命预测的可行性。结果表明,当裂纹在粗晶热影响区(CGHAZ)和临界热影响区(ICHAZ)上扩展时,由实际焊接试样与焊接热模拟试样热影响区所测得的疲劳裂纹扩展速率曲线(da/d N-#K曲线)存在明显差异,其原因与显微组织变化引起的裂纹扩展阻力大小不同有关。因此,建议采用实际焊接试样完整的热影响区所测得的da/dN-#K曲线来评估疲劳裂纹扩展寿命。Fatigue crack propagation behavior in each heat affected zone(HAZ)of X80 dual-phase pipeline steels was investigated by using welding thermal simulation.The differences of the fatigue cracks propagation behavior between real welded and welding thermal specimens were also analyzed.And the feasibility on the prediction of fatigue cracks propagation life for applying welding thermal simulation was discussed.The results show that there is an obvious contrast between the fatigue crack growth rate curves(da/d N-#K curves)of the real welded and welding thermal specimens when the cracks are propagated in the CGHAZ and ICHAZ,which are attributed to variations of the microstructure change,thus leading to the change of cracks propagation resistance.Therefore,it is recommended to predict the fatigue crack propagation life through the da/d N-#K curve of integrated HAZ in the real welded specimens.

关 键 词：焊接热模拟 热影响区 疲劳裂纹扩展 X80管线钢 

分 类 号：TG441[金属学及工艺—焊接]