t_(8/5)对高强度余热处理棒材焊接热影响区组织和力学性能的影响  

Effects of t_(8/5) on Microstructure and Mechanical Properties of Weld Heat-Affected Zone of High-Strength Residual Heat Treatment Steel Bar

作　　者：肖轶[1,2,3] 方建慧[1] 钟庆东[1] 刘卫东[1,3] 

机构地区：[1]上海大学上海市现代冶金与材料制备重点实验室,上海200072 [2]南通职业大学机械工程学院,南通226007 [3]南通市钢铁冶金过程控制工程技术研究中心,南通226002

出　　处：《机械工程材料》2014年第11期99-103,共5页Materials For Mechanical Engineering

基　　金：国家科技支撑计划项目(2008BAG07B03);南通市应用研究计划项目(BK2013033);南通市瞪羚计划项目(AA2012021)

摘　　要：采用Gleeble-3500型热模拟试验机研究了不同t8/5对高强度余热处理棒材焊接热影响区（HAZ）显微组织和力学性能的影响。结果表明：随着t8/5增大,粗晶热影响区（CGHAZ）的组织由羽毛状上贝氏体、短条状下贝氏体和铁素体转变为粒状贝氏体、珠光体和铁素体;HAZ的室温冲击功先增大后减小,并在t8/5=100s时达到最大;当t8/5〉60s后,CGHAZ组织由珠光体和铁素体组成;HAZ的硬度随着t8/5增大而降低;高强度余热处理棒材能够满足实际生产需要的t8/5区间为20~300s。The effects of different t8/5on microstructure and mechanical properties of heat-affected zone（HAZ）of high-strength residual heat treatment steel bar were studied by using Gleeble-3500 welding thermal simulation tester.The results show that,with the increase of t8/5,the microstructure of coarse grain heat-affected zone（CGHAZ）changed from feather-like upper bainite,strip-like lower bainite and ferrite to granular bainite,pearlite and ferrite.The impact energy of heat-affected zone at room temperature increased firstly then decreased and reached the maximum when t8/5=100s.When t8/5was more than 60 s,the microstructure of CGHAZ was made of ferrite and pearlite.The micro-hardness of heat-affected zone decreased with the increase of t8/5.The high-strength residual heat treatment steel bar would be meet the production needs with the range of t8/5from 20 sto 300s.

关 键 词：余热处理 棒材 焊接热输入 焊接热影响区 显微组织 冲击韧性 显微硬度 

分 类 号：TG444.1[金属学及工艺—焊接]