摘要
通过轧制真空复合板,分析热轧工艺对304不锈钢焊缝微观组织及残余应力的影响,压下率分别为:0%、10%、20%、30%、30%/20%。结果表明:随着轧制压下率的增加,晶粒分布逐渐均匀,平均晶粒直径由150.3μm减小至77.9μm;部分大角度晶界转变为小角度晶界(LAGB),LAGB占比由62.0%增加至89.6%;LAGB阻碍位错运动,使得位错在LAGB处聚集,几何必需位错密度由1.32×10^(13)m^(-2)增加至3.61×10^(13)m^(-2);位错密度的增加导致材料内部晶格畸变程度增加,材料内部应力状态发生改变,残余应力由23.7 MPa的残余拉应力转变为114.3 MPa的残余压应力。
The influence of hot rolling process on the microstructure and residual stress of 304 stainless steel welds was investigated using a rolling vacuum composite plate,with rolling reduction ratios set at 0%,10%,20%,30%,and 30%/20%.The results show that,as the rolling reduction ratio increases,the grain distribution becomes progressively uniform,and the average grain size diminishes from 150.3μm to 77.9μm;a portion of high-angle grain boundaries transforms into low-angle grain boundaries(LAGB),with the proportion of LAGB rising from 62.0%to 89.6%;these LAGB impede dislocation movement,causing dislocations to accumulate at the LAGB,and the density of geometrically necessary dislocations increases from 1.32×10^(13)m^(-2)to 3.61×10^(13)m^(-2);the increased dislocation density leads to greater lattice distortion within the material,altering its internal stress state,resulting a stress transition from residual tensile stress of 23.7 MPa to residual compressive stress of 114.3 MPa.
作者
陈璇
乔建英
李海斌
智俊杰
帅美荣
王建梅
CHEN Xuan;QIAO Jianying;LI Haibin;ZHI Junjie;SHUAI Meirong;WANG Jianmei(High-end Heavy Machinery and Equipment Research Institute,Taiyuan University of Science and Technology,Taiyuan 030024,China;State Key Laboratory of Advanced Stainless Steel,Taiyuan University of Science and Technology,Taiyuan 030024,China;Shanxi Chengshuang Flange Co.,Ltd.,Xinzhou 035499,China;Shanxi Institute of Technology,Yangquan 045000,China)
出处
《热加工工艺》
北大核心
2025年第24期27-35,共9页
Hot Working Technology
基金
国家自然科学基金资助项目(51875382)
太原市关键核心技术攻关“揭榜挂帅”项目(2024TYJB0114)
忻州市重点研发计划项目(20240103)。
关键词
304不锈钢焊缝
真空热轧
微观组织
几何必需位错密度
残余应力
304 stainless steel weld
vacuum hot rolling
microstructure
geometrically necessary dislocation density
residual stress
