Sn对C-Mn钢焊接组织与脆性的影响  

Effect of Sn on Welded Microstructure and Brittleness of C-Mn Steel

作　　者：周明荣[1] 张宇本[1] ZHOU Mingrong;ZHANG Yuben(Zhejiang Industry Polytechnic College,Shaoxing 312000,China)

机构地区：[1]浙江工业职业技术学院,浙江绍兴312000

出　　处：《铸造技术》2018年第10期2340-2344,共5页Foundry Technology

基　　金：浙江省建设厅科研资助项目(2014Z133)

摘　　要：对C-Mn和C-Mn-Sn钢进行了焊接热模拟试验,研究了不同焊接线能量下Sn元素对建筑用钢显微组织、物相组成和韧-脆转变温度的影响,并分析了Sn的晶界偏聚行为及对焊接接头热影响区脆化作用的影响。结果表明,随着焊接线能量的增加,C-Mn和C-Mn-Sn钢的韧-脆转变温度都呈现为先增加而后降低的趋势;焊接线能量为36 kJ/cm时,Sn对焊接热影响区起到了明显的脆化作用,而在焊接线能量为60 kJ/cm和100 k J/cm时,Sn的存在并没有使焊接热影响区明显脆化;当焊接线能量为36 k J/cm时,C-Mn-Sn钢中Sn晶界浓度修正值为0.77at.%;焊接线能量为60 kJ/cm和100 kJ/cm时,C-Mn-Sn钢中晶界的破坏使得晶界偏聚和由晶界Sn偏聚引起的脆化作用消失;在三种焊接线能量下,含Sn的C-Mn-Sn钢的显微硬度都要小于不含Sn的C-Mn钢。The welding thermal simulation test of C-Mn and C-Mn-Sn steel was carried out, the effect of Sn element on the microstructure, phase composition and ductile brittle transition temperature of steel for construction with different welding line energy were studied, and the behavior of grain boundary segregation of Sn and its effect on the embrittlemeut of the heat affected zone of welded joints were analyzed. The results show that the ductile brittle transition temperature of C-Mn and C-Mn-Sn steels is increased at first and then decreased with the increase of the welding line energy. When the welding line energy is 36 kJ/cm, Sn has a clear effect on the welding heat affected zone, and the existence of Sn does not make the welding heat affected zone obviously brittle when the welding line energy is 60 kJ/cm and 100 kJ/cm. When the welding line energy is 36 kJ/cm, and the modified value of grain boundary concentration of Sn is 0.77at%. When the energy of welding wire is 60 kJ/cm and 100 kJ/cm, the failure of grain boundary in C-Mn-Sn steel makes the disappearance of the grain boundary segregation and the embrittlement caused by the Sn segregation at the grain boundaries. In three kinds of welding line energy, the microhardness of C-Mn-Sn containing Sn steel is less than that of C-Mn Sn steel.

关 键 词：元素Sn C-MN钢 热影响区 脆化 显微组织 

分 类 号：TG454[金属学及工艺—焊接] TG113