金属加工（热加工）Issue(3)：70-75,6.
预热温度对深水导管架高强钢S420焊缝延迟裂纹的影响
Influence of preheat temperature on delayed crack in weld joint of high-strength steel S420 for deep-water jacket
摘要
Abstract
During the actual welding of the high-strength steel S420 for deep-water jacket,the flux cored welding wire is often exposed to the humid air environment,resulting in an increase in the content of diffusing hydrogen,and the weld metal is easy to occur delayed cracks.The influence of different preheat temperature on delayed crack sensitivity of weld metal is studied by diffusing hydrogen test and oblique Y-groove test,then the microstructure characteristics,hardness and crack initiation/growth behavior are analyzed.The results show that the diffusive hydrogen content increases from 4.0mL/100g to 7.0mL/100g with the exposure of welding materials in wet environment.There is no delayed crack on the weld,when the welding material is not exposed and the preheat temperature is 130℃.The crack rate of weld metal is up to 25%,after the welding material is exposed for 24h and the preheat temperature is 130℃.When the preheat temperature increases to 150℃,there is no delayed crack in the weld.In order to effectively prevent welding delay cracks in thick and high-strength steel S420,in addition to considering carbon equivalent,plate thickness,and heat input,it is also necessary to consider the increase in diffusion hydrogen content caused by the exposure of welding materials in the welding environment,and then determine a reasonable preheating temperature.关键词
预热温度/高强钢/扩散氢/延迟裂纹Key words
preheat temperature/high-strength steel/diffusing hydrogen/delayed crack引用本文复制引用
王艳,王心悦,徐燕铭,李珍,吴世品..预热温度对深水导管架高强钢S420焊缝延迟裂纹的影响[J].金属加工（热加工）,2025,(3):70-75,6.基金项目
天津海运职业学院校级课题(XJ2023-Z-02) （XJ2023-Z-02）
天津市教委科研计划项目(2020KJ104). （2020KJ104）
