【摘要】 采用高频感应焊接技术对壁厚为0.28 mm的3003铝合金进行焊接，研究了焊接接头的微观组织和力学性能。结果表明，焊接接头晶粒细小，是焊接过程中感应加热与挤压同步进行，局部晶粒发生塑性变形从而抑制了晶粒长大所致；焊接接头熔合区呈上下宽、中间窄的窄腰状，宽度为6～10μm,熔融区呈细腰鼓形，单侧宽度为24～49μm,其相邻两侧的热影响区部分发生再结晶，宽度为115～127μm;断口形貌显示焊接接头断裂类型为以韧性断裂为主的韧脆混合型断裂，其抗拉强度为242 MPa,达到带材的91%,伸长率为15%,略低于带材(23%);焊接接头各区域硬度值呈M形对称分布，熔融区与热影响区硬度值明显高于母材区，熔融区最高，达到85.27HV,热影响区约为79.33HV,熔合区硬度值最低，为55.85HV。与母材相比，焊接接头强度和硬度分布规律与各区域晶粒大小和第二相种类及分布有关。更多还原

【Abstract】 The microstructure and mechanical properties of high frequency induction welding joints of 3003 aluminum alloy with wall thickness of 0.28 mm were studied. The results show that the grain size of the welded joint is fine, which is caused by the simultaneous induction heating and extrusion in the welding process, resulting in the plastic deformation of local grains, thereby inhibiting the grain growth. The fusion zone is a narrow waist shape with a width of 6—10 μm, the melting zone with unilateral width of 24—49 μm is thin waist drum-shaped, and the heat affected zone on adjacent sides is partially recrystallized, with width of 115—127 μm. The fracture morphology shows that the fracture type of the welded joint is ductile brittle mixed fracture dominated by ductile fracture. Its tensile strength is 242 MPa, which reaches 91% of the strip, and the elongation is 15%, which is slightly lower than that of the strip(23%). The hardness values of each region of the welded joint were distributed in M-shaped symmetry. The hardness values of the melting zone and the heat affected zone were significantly higher than those of the base metal zone. The hardness value of the melting zone was the highest, reaching 85.27HV, and that of the heat affected zone was about 79.33HV. The hardness value of the fusion zone was the lowest, only 55.85HV. Compared with the base metal, the strength and hardness distribution of welded joints are related to the grain size and the type and distribution of the second phase in each region.更多还原