焊接线能量对高强钢焊接接头组织性能的影响  

Influence of welding energy inputs on microstructure and performance of welding joint of high strength steel

作　　者：梁亮 张波[3] 邓想涛 刘旭辉[2] 肖爱达[2] 欧玲[3] LIANG Liang;ZHANG Bo;DENG Xiang-tao;LIU Xu-hui;XIAO Ai-da;OU Ling(State Key Laboratory of Rolling Technology and Automation,Northeastern University,Shenyang 110819,China;Center for Product and Technology,Hunan Valin Lianyuan Iron and Steel Company,Loudi 417009,China;School of Metallurgical Engineering,Hunan University of Technology,Zhuzhou 412000,China)

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110819 [2]湖南华菱涟源钢铁有限公司技术中心,湖南娄底417009 [3]湖南工业大学冶金与材料工程学院,湖南株洲412000

出　　处：《轧钢》2020年第2期12-17,共6页Steel Rolling

基　　金：湖南省重点研发计划资助项目(2017GK2262)。

摘　　要：采用1.3、1.6、1.9 kJ/mm 3种不同线能量对960QT钢进行焊接,研究了线能量对960QT钢焊接接头组织和性能的影响。研究表明,随着线能量的增加,焊接接头强度下降,但塑性提高,焊缝冲击韧性变化不大,热影响区冲击韧性先降低后增大,热影响区冲击韧性均高于焊缝。对3种线能量下960QT高强钢的焊接接头进行金相分析,发现焊缝组织主要为针状铁素体和粒状贝氏体。随着线能量的增加,针状铁素体发生粗化,数量相对减少,粒状贝氏体数量增多。焊接接头热影响区的金相组织主要为板条M/B和粒状贝氏体。随着焊接线能量的增大,冷却速率减小,粒状贝氏体组织数量相对增加,而板条贝氏体组织的数量逐渐减少。960 QT steel was welded with three different energy inputs of 1.3、1.6、1.9 kJ/mm.The influence of energy inputs on the microstructure and properties of 960 QT steel’s welding joint was studied.The results show that with the increase of energy inputs,the strength of welding joint decreases,but the plasticity increases,the impact toughness of welding seam does not change much,and the impact toughness of heat affected zone decreases first and then increases.The impact toughness of the heat affected zone is higher than that of the welding seam.Metallographic analysis of welding joint of 960 QT high strength steel under three energy inputs show that the welding seam microstructure is mainly acicular ferrite and granular bainite.As the energy inputs increases,the acicular ferrite coarsens,the amount decreases,and the number of granular bainite increases.The metallographic structure of the heat affected zone of the welding joint is mainly lath M/B and granular bainite.As the welding energy inputs increases,the cooling rate slows down,the number of granular bainite structures increases,and the number of lath bainite structures decreases.

关 键 词：960QT钢 焊接线能量 微观组织 冲击韧性 

分 类 号：TG457.11[金属学及工艺—焊接]