Mn和Ni对低碳焊材组织与力学性能的影响  

Effects of Mn and Ni on Microstructure and Mechanical Properties of Low Carbon Welding Material

作　　者：季业益[1] 王玉玲[2] 李强伟[3] 

机构地区：[1]苏州工业职业技术学院精密制造工程系,江苏苏州215003 [2]烟台大学材料工程学院,山东烟台264005 [3]苏州大学工程训练中心,江苏苏州215123

出　　处：《热加工工艺》2017年第3期45-49,共5页Hot Working Technology

基　　金：江苏省高等职业院校高级访问工程师计划资助项目(2015FG038);江苏高校品牌专业建设工程资助项目(PPZY2015B186)

摘　　要：开发了含碳量极低,含Mn、Ni的金属焊线。使用该金属焊线在Ar-2%O_2保护气氛中制备得到不同Mn、Ni含量的低碳焊接金属,并测试其组织和力学性能。结果表明:随着Ni含量的增大,无论低Mn还是高Mn的焊层柱晶区微观组织均出现板条马氏体相,晶界铁素体含量降低。低Mn和低Ni高Mn的焊层再加热区微观组织均以铁素体为主;随着Ni含量的增加,高Mn焊层再加热区的柱状晶含量增大。焊材金属硬度与Mn和Ni含量的增加呈线性关系。Ni影响焊层的冲击性能,其变化取决于Mn含量。Mn含量低时,Ni增加硬度但不会降低冲击韧性;Mn含量高时,较大含量的Ni严重地恶化冲击韧性,引起沿晶断裂。为了获得较高的硬度与冲击韧性,焊材金属Mn与Ni的最佳含量分别为0.5%~1%和4%~5%。The metal wire with a very low content of carbon including Mn, Ni was developed. Low carbon weld metals with different contents of Mn and Ni were prepared by the metal wire in Ar-2%O2 atmosphere, and the microstructure and mechanical properties were tested. The results show that with the increase of Ni content, lath martensite is found in the microstructure of columnar grain zone of low Mn and high Mn welding layers, and the content of grain boundary ferrite reduces. The microstructure in reheating zone of welding layers with low Mn and low Ni high Mn is mainly ferrite. With the increase of Ni content, the content of columnar grains in reheating zone of high Mn welding layer increases. There is a linear relation between the hardness of welding metal and the content of Mn and Ni. Ni affects the impact property of welding layer, and its variation depends on the content of Mn. When the Mn content is low, Ni increases the hardness, and it does not reduce the impact toughness. When the Mtt content is high, a large content of Ni severety deteriorates the impact toughness,which induces intergranular fracture. In order to obtain high hardness and impact toughness of welding metal, the optimum content of Mn and Ni are 0.5%-1% and 4%-5% respectively.

关 键 词：硬度 冲击韧性 铁素体 板条马氏体 

分 类 号：TG422[金属学及工艺—焊接]