6082-T6铝合金等离子-CMT复合热源焊接特性研究

Research on the welding characteristics of plasma-CMT hybrid welding for 6082-T6 aluminum alloy

以6 mm厚6082-T6铝合金为试验母材开展等离子-CMT复合焊接试验,分析焊接工艺参数对焊缝成形的影响规律,以及接头的组织特征、硬度分布及拉伸性能。获得最优焊接工艺参数为:等离子电流130 A、送丝速度8 m/min、焊接速度50 cm/min,等离子气流量7 L/min。焊缝中心组织主要为等轴晶,热影响区较窄且硬度值最低,接头平均抗拉强度达228.4 MPa,为母材抗拉强度的77.4%,断裂位置在焊接接头的热影响区,呈现韧性断裂特征。

In the present work,6082-T6 aluminium alloy with a thickness of 6 mm was used as the base material,and the plasma-CMT hybrid welding was carried out. The effect of welding parameters on the weld formation was studied. The microstructure characteristic,hardness distribution and tensile property of the plasma-CMT hybrid welded joint were also researched. The optimized welding parameters obtained were as follows:plasma current 130 A,wire feeding speed 8 m/min,welding speed 50 cm/min and plasma gas flow 7 L/min. The fine equiaxed grain was found in the weld center. The heat affected zone was very narrow and had the lowest hardness value. The tensile tests results showed that tensile strengths of the welded joint could reach up to 228.4 MPa,which was77.4% of that of the base material. The tensile test fracture area located on the heat affected zone,and the tensile fracture morphology was characterized by ductile fracture.