摘要
采用等离子熔焊,能量密度相对集中,焊接效率高,选用热收缩率较低的材料可显著提高铸铁的焊接强度。研究通过铸铁粉末等离子熔焊进行灰铸铁的焊接,探究不同电流对焊缝组织和性能的影响,通过扫描电镜分析焊缝组织,XRD表征焊缝相组成,显微硬度分析焊缝部分的硬度,拉伸试验测试焊接接头的拉强度。结果表明:焊缝区显微组织由马氏体、珠光体、残余奥氏体和少量二次碳化物组成,电流的提高增加了焊缝区珠光体含量和结合区宽度,但稀释率也增加,当电流为110A时,稀释率达到最高值32.89%。焊接电流100A时,接头的抗拉强度最高213MPa,稀释率14.7%,较高的珠光体含量5.34%,是最优的工艺参数。
Plasma fusion welding is featured by high energy density and welding efficiency.Selecting the low thermal shrinkage material can obviously improve the welding strength of cast iron.In the study the cast iron powders were used to weld the grey cast iron by plasma welding,the influences of different currents on microstructure and properties of weld microstructure were investigated.Scanning electron microscopy(SEM)and X-ray diffraction(XRD)were used to determine the microstructure and phase composition of weld microstructure.The microhardness and tensile strength were analyzed by the microhardness tester and tensile tester.The results show that the microstructure of the weld metal consists of martensite,pearlite,retained austenite and a small amount of secondary carbide.The welding current is increased,the amount of pearlite in the joint and width of bonding zone is enhanced simultaneously,but dilution rate is also increased.when the current reaches 110A with the highest dilution rate 32.89%.The welding current reaches 100A with the high tensile strength 213MPa,dilution rate 14.7%and higher content of pearlite 5.34%is the best process parameter.
作者
陈白阳
高培虎
贾涵
李建平
李晓航
王喜锋
杨忠
郭永春
李全平
CHEN Baiyang;GAO Peihu;JIA Han;LI Jianping;LI Xiaohang;WANG Xifeng;YANG Zhong;GUO Yongchun;LI Quanping(School of Materials and Chemical Engineering,Xi’an Technological University,Xi’an 710021,China;Representative Office in Xi’an,PLA,Xi’an 710032,China;Shanxi Disel Engine Industry Company Ltd,Datong 037036,China)
出处
《沈阳理工大学学报》
CAS
2020年第2期35-40,59,共7页
Journal of Shenyang Ligong University
基金
国家自然科学基金资助项目(51771140)
陕西省创新人才推进计划-科技创新团队(2017KCT-05)
陕西省自然科学基金项目(2018JM5003,2018JM5070)
陕西省教育厅服务地方计划专项项目(19JC022)
陕西高校“金属腐蚀防护及表面工程技术”青年创新团队。
关键词
灰铸铁
等离子焊接
组织
性能
grey cast iron
plasma welding
microstructure
property
