含Mg药芯焊丝对SiCp/6061Al等离子弧原位焊接的影响  

Effects of magnesium flux cored wire on plasma arc "in-situ" welding of SiCp/6061Al MMCs

作　　者：雷玉成[1,2] 刘珍珍[1] 王志伟[1] 薛厚禄[1] 闫久春[2] 

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013 [2]哈尔滨工业大学先进焊接与连接国家重点实验室,哈尔滨150001

出　　处：《材料科学与工艺》2011年第6期33-38,共6页Materials Science and Technology

基　　金：哈尔滨工业大学先进焊接与连接国家重点实验室资助项目(09003);江苏省焊接技术重点实验室资助项目(JSAWT-09-03);江苏大学科技创新团队资助项目

摘　　要：针对SiCp/6061Al基复合材料焊接接头中增强相颗粒发生偏聚,使接头强度降低的问题,采用不同Mg含量的药芯焊丝(合金元素Al-Ti-Mg)为填加材料,以氩氮混合气为离子气,对SiCp/6061Al基复合材料进行等离子弧原位合金化焊接,研究了该类药芯焊丝对焊接接头组织和性能的影响.研究表明,当焊丝中Mg含量达到15%时,电弧燃烧不稳定,飞溅严重,焊缝成型差,焊缝中有脆性相Mg2Si生成;当Mg≤5%时,电弧能稳定燃烧,无飞溅,焊缝外观成形良好,焊缝组织致密,AlN、TiN和TiC等新生相较为细小,无脆性相Mg2Si和Al4C3产生,接头强度和韧性有所提高,抗拉强度达到213 MPa,为母材强度的67%.拉伸断口分析显示接头具有一定的韧性,但总体上仍表现为脆性断裂.To sovle the problem of segregation of reinforcement particles in joint of SiCp/6061Al MMCs,which makes the tensile strength decreased,the SiCp/6061Al Matrix Composites were welded by plasma arc welding with flux cored wires in different magnesium content as filled composite and argon-nitrogen mixture as plasma gases,and the effect of this kind of flux cored wire on the microstructure and properties of welded joints was investigated.The results show that,with the mass fraction of magnesium reaches to 15% in wire,a poor welded-joint,serious splash and unstable arc will appeare,however,when it is less than 5%,a good and compact weld metal with stable arc and no splash will form.At the same time,the new phases of AlN,TiN and TiC are small,neither Mg2Si nor Al4C3 are found in the joint.All the strength and toughness of the joint have been improved.The maximum tensile strength of welded joint increases to 213 MPa,67% of the matrix.Generally,the tensile fracture is brittleness fracture with a little toughness.

关 键 词：等离子弧焊接 力学性能 SiCp/6061Al基复合材料 新生增强相 

分 类 号：TG456.2[金属学及工艺—焊接] TG407