硅对SAl5356铝合金焊丝显微组织和性能的影响  

Effect of Si on microstructures and properties of SAl5356 a-luminum alloy wire

作　　者：黄杰[1] 薛松柏[1] 顾荣海[1] 王博[1] 林中强 

机构地区：[1]南京航空航天大学材料科学与技术学院,南京210016 [2]浙江宇光铝材有限公司,武义321200

出　　处：《焊接学报》2015年第11期69-72,116,共4页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51375233);江苏高校优势学科建设工程资助项目

摘　　要：研究了硅对SAl5356焊丝及其焊接的5083铝合金焊缝显微组织及力学性能的影响.结果表明,Si元素含量在0-0.12%时,随着Si元素含量的增加,SAl5356焊丝及其焊接接头强度稍有升高,塑性稍有下降;当Si元素含量高于0.12%时,随着Si元素含量的增加,SAl5356焊丝及其焊缝组织中含硅粗大相增多,焊丝拉伸性能下降,硬度不均匀性加剧,焊接接头强度及弯曲性能变差.特别是当Si元素含量超过0.2%后,合金中含硅粗大相在晶界处富集,与α（Al）基体构成鱼骨状共晶组织,焊丝及其焊接接头力学性能下降更加明显,铝线材的强度比峰值下降了约12%,断后伸长率下降了约45%.因此从提高SAl5356焊丝及其焊缝性能角度考虑,Si元素含量不宜超过0.2%,以控制在0.12%以内最佳.The effects of the addition of Si on the microstructures and properties of SAl5356 aluminum alloy wire and its tensile properties of butt-welded joints with SAl5356 as the filler were investigated. Results showed that,when the content of Si ranged from 0 to 0. 12%,the tensile strength of SAl5356 wire and its welded joint was improved slightly with the increase of Si content,while the plasticity was just the opposite. When the content of Si was higher than 0. 12%,some coarse silicon rich phases were found in the microstructures of SAl5356 wire and its weld,and all properties,especially plasticity,dropped with the increase of Si content. In particular,when the Si content was above 0. 2%,the coarse silicon rich phases were enriched at the grain boundaries,and forming fish-bone-shaped eutectic structure with α( Al) matrix,and their tensile properties dropped more obviously. The tensile strength of SAl5356 aluminum rod with Si content 0. 25% was decreased 12% from its peak,while the elongation was decreased 45% from its peak. Therefore,to improve the performance of SAl5356 aluminum wire and its weld,Si content should not be more than 0. 2%,and the optimum content of Si was less than 0. 12%.

关 键 词：SI元素 5356铝焊丝 显微组织 力学性能 

分 类 号：TG457.14[金属学及工艺—焊接]