7075铝合金等离子-MIG复合焊接接头热裂纹数值模拟  

Numerical simulation of hot cracking of 7075 Al alloy by plasma-MIG hybrid welded joint

作　　者：李丽琼 金成[1] LI Liqiong;JIN Cheng(School of Material science and Engineering,Dalian Jiaotong University,Dalian 116028,China)

机构地区：[1]大连交通大学材料科学与工程学院

出　　处：《电焊机》2019年第7期95-100,共6页Electric Welding Machine

摘　　要：针对7075铝合金等离子-MIG复合焊接过程中热裂纹产生的宏、细观原因问题,采用鱼骨法进行焊接热裂纹敏感试验。使用直径φ1.2mm的ER5356铝合金焊丝对厚度4mm的7075-T6铝合金板材进行等离子-MIG复合焊接试验,测定7075-T6铝合金脆性温度区间(BTR),评定其热裂纹倾向。采用宏观热弹塑性结合细观晶体塑性有限元法数值模拟,结果表明略微的应变差会导致热裂纹敏感性的不同,故此提出适当的调节应变差,优化焊接工艺过程。Aiming at the macroscopic and mesoscopic causes of hot cracking in the 7075 aluminum alloy plasma-MIG hybrid welding process. Fishbone cracking test was applied to test the welding hot cracking sensitivity. 7075-T6 aluminum alloy sheet with 4mm thickness was welded by Plasma-MIG hybrid welding method using ER5356 aluminum alloy wire with φ1.2mm diameter. The brittle temperature range (BTR) of the 7075-T6 aluminum alloy was measured and the hot cracking tendency was evaluated. Combing macroscopic thermoelastic-plastic method and mesoscopic crystal plastic finite element method, the numerical simulations results show that a slight strain difference will lead to the different hot cracking sensitivity, so the appropriate adjustment of the strain difference is proposed to optimize the welding process.

关 键 词：热裂纹 等离子-MIG复合焊接 晶体塑性有限元 

分 类 号：O343.6[理学—固体力学]