1000 MPa级高强钢激光-电弧复合焊接头组织及氢脆行为研究
Study on the Hydrogen Embrittlement Behavior of 1 000 MPa Grade Bainite High Strength Steel Laser-Arc Hybrid Weld Joint
岳巧红 1杨东1
作者信息
摘要
采用"四点弯曲加载-原位电化学充氢"实验方法,结合微观组织分析和断裂特征分析,研究了 1 000 MPa级低碳贝氏体高强钢激光-电弧复合焊接头的氢脆行为.结果表明,激光-电弧复合焊接过程形成的高温度梯度导致热影响区内发生马氏体相变,并且在细晶区内形成较高的焊接残余应力.马氏体组织的高氢脆敏感性、晶界的高氢扩散性以及局部焊接残余应力梯度促进细晶区内沿马氏体萌生氢脆裂纹并沿晶界快速扩展而发生脆性断裂.
Abstract
In this paper,the hydrogen embrittlement behavior of laser-arc hybrid welded joint of bainite high strength steel was studied by four-point bending loading under in-situ electrochemical hydrogen charging combined with microstructure analysis and fracture characteristics analysis.The result show that the high temperature gradient during laser-arc hybrid welding leads to martensite transformation in the heat-affected zone,and high welding residual stress is formed in the fine grain zone.The martensitic phase's susceptibility to hydrogen embrittlement,coupled with the high diffusivity of hydrogen along grain bounda-ries and the localized residual stress gradients,facilitates the nucleation and growth of hydrogen-induced cracks.This process is predominantly observed along the martensitic laths and grain boundaries,culminating in a brittle fracture mode.
关键词
激光-电弧复合焊/高强钢/氢脆/微观组织Key words
laser-arc hybrid welding/high strength steel/hydrogen embrittlement/microstructure引用本文复制引用
基金项目
郑州市电子信息功能材料及器件重点实验室(121PYFZX178)
出版年
2024
NETL
NSTL
万方数据