作　　者： (曾锋）;

机构地区： 广东工贸职业技术学院,广东广州510510

出　　处： 《机械设计与制造》 2017年第9期152-154,共3页

摘　　要： 采用脉冲熔化极惰性气体保护焊实现铸造铝合金和锻造铝合金的搭接。搭接焊缝中大量的气孔严重影响了接头的力学性能。研究目的是研究搭接焊缝中气孔的分布,成因以及控制措施。研究发现通过改变焊枪倾角和保护气体的成分可以实现减少气孔提高接头性能的目的。通过高速摄影观察发现减小焊枪倾角可以改变焊接过程中熔池的形态,从而起到减少气孔的目的。同时,保护气体中加入适量的He和CO_2也能够减少焊缝中的气孔数量。最终,保护气体为39%Ar+1%CO_2+60%He,焊枪倾角为40°被确定为最佳工艺。 In this paper, gas metal arc welding （GMAW） was employed to weld lap fillet joint between cast and wrought Al alloys. The porosities are the main reason that causes the drop of mechanical properties of lap fillet welded joint. The aim of this paper is to study the effect of torch angels and shielding gases on porosity distribution and morphology in welded joint. It is found that decreasing the torch angle helps in reducing porosity and improve the mechanical properties , High-speed photography shows that decreasing torch angle can chan@ the molten pool shape, which can effectively lreduce porosities. Addition of Helium （He） into the shielding gas decreases the porosities in weld joint because the increasingof arc temperature can improve the welding heat input, especially with Argon （Ar）＋He＋CO2 gas mixture.39% Ar＋ 1 %CO2＋60% He shielding gas and 40° torch angle are identified as the most optimum process parameters in reduction porosity in GMAW welding on the Al alloy lap fillet welds.

关 键 词： 铝合金 焊缝 气孔 焊枪倾角 保护气体