摘要
在三种热输入下进行了高强耐候钢药芯焊丝电弧焊,利用光学显微镜和扫描电镜分析了焊缝和热影响区组织,并对焊接接头的强度、硬度和-40°冲击吸收能量进行了分析。结果表明,三种热输入下,焊缝组织主要以针状铁素体为主,热影响区组织均为板条贝氏体加粒状贝氏体,并且随热输入增大,焊缝和热影响区组织有一定粗化。在小热输入0. 74 kJ/mm和中等热输入0. 96 kJ/mm下,焊缝金属的强度和塑性与母材相当;在大热输入1. 19 kJ/mm下,焊缝位置发生了脆化。在三种热输入下,焊接热影响区的冲击吸收能量均低于焊缝区,焊缝和热影响区均为韧/脆混合断裂模式。
Flux-cored arc welding of high strength weathering steel was carried out at three different heat input. Microstructures of weld metal and heat-affected zone( HAZ) were observed by optical microscope( OM) and scanning electron microscope( SEM). And the strength,hardness and impact toughness at-40 ° were analyzed. The results indicate that the microstructure in weld metal is mainly consisted of fine-grain acicular ferrite and that in HAZ is composed of lath bainite and granular bainite. With increase of heat input,microstructures become certainly coarser. At the lower heat input of 0. 74 kJ/mm and middle heat input of 0. 96 kJ/mm,the strength and plasticity of weld metal are matched with base metal. At the higher heat input of 1. 19 kJ/mm,embrittlement occurs in weld metal. At three different heat input,impact absorbing energy of HAZ is lower than that of weld metal. Fracture mode is tough/brittle hybrid fracture in both weld metal and HAZ.
作者
武永亮
焦辉
易冉
杨卫东
Wu Yongliang;Jiao Hui;Yi Ran;Yang Weidong(CRRC Yangtze Group Co.,Ltd.,Zhuzhou 412003,Hunan China)
出处
《焊接》
2019年第2期59-64,68,共7页
Welding & Joining
关键词
热输入
高强耐候钢
药芯焊丝电弧焊
组织
heat input
high strength weathering steel
flux-cored arc welding
microstructure
