Microstructure and Impact Toughness of the Intercritically Reheated Coarse-grained Heat Affected Zone of 13MnNiMoR Steel

摘要：

　　The microstructure and impact toughness of intercritically reheated coarse-grained heat affected zone(ICCGHAZ)of 13MnNiMoR and the effect of post-welding heat treatment(PWHT)process were investigated by means of welding thermal simulation test.The result shows that after the first welding thermal cycle,the microstructure of the coarse-grained heat affected zone(CGHAZ)mainly consists of granular bainite and lath bainite,with good impact toughness.After the second thermal cycle with a peak temperature of 650 to 700℃,the CGHAZ microstructure experiences a tempering process and its impact toughness improves due to the precipitation of carbides and reduction of dislocations.With a second peak temperature of 750 to 850℃,part of the CGHAZ microstructure retransforms to austenite and during cooling,martensite-austenite(MA)constituents forms along grain boundaries in the ICCGHAZ microstructure,leading to a sharp drop of toughness.When the second thermal cycle peak temperature is up to 900℃,the CGHAZ microstructure is fully austenitized,and the final microstructure mainly consists of ferrite and granular bainite.After a PWHT process in the temperature range of 560 to 640℃,the impact toughness of ICCGHAZ is markedly improved,primarily due to the decomposition of MA constituents.

关键词： 13MnNiMoR welding thermal simulation intercritically reheated coarse-grained heat-affected zone post-welding heat treatment impact toughness

作者: YANG Han QU Jinbo

作者单位: Institute of Research of Iron and Steel of Sha-steel,Zhangjiagang 215625,Jiangsu,China

会议类型: 国际会议

会议名称: Energy Materials 2014(第一届能源材料国际会议)

会议地点: 西安

会议语种:英文

页码: 887-894

在线出版日期: 2014-11-04（万方平台首次上网日期，不代表论文的发表时间）