7A04铝合金/304不锈钢连续驱动摩擦焊及焊后热处理

对7A04铝合金与304不锈钢异种材料进行了摩擦焊接试验，并对接头进行了不同温度、不同时间的退火处理.对接头飞边形貌、抗拉强度、断口形貌、金相组织、显微硬度等进行对比分析.结果表明，采用合适的工艺参数能获得形貌良好的飞边和更好的抗拉强度，焊合区的铝合金组织发生动态再结晶，晶粒细化，组织比基材更加致密，结合面两边互有元素扩散，焊合区显微硬度高于基材.经400℃×3 h退火处理的接头其抗拉强度提升明显，界面形成了不同的金属间化合物，扩散层厚度略有增加，显微硬度值有所下降.

Continuous drive friction welding and post welding heat treatment of 7A04 aluminum alloy and 304 stainless steel

The 7A04 aluminum alloy and 304 stainless steel dissimilar materials are welded by continuous drive friction welding, and the joints were annealed at different temperature and different time. The burr morphology, tensile strength, fracture morphology, microstructure and micro-hardness of joints were analyzed. Using the appropriate process parameters can obtain good shape of the edge fin and better tensile strength, the microstructure of aluminum alloy of weld zone is dynamic recrystallization, grain refinement, and the structure is more dense than the substrate, element diffusion occurs on both sides of the bonding surface, the microhardness of weld zone is higher than that of the substrate. The tensile strength of the joints treated by 400℃×3 h annealing is obviously improved, different intermetallic compounds were formed at the interface, diffusion layer thickness increased slightly, the microhardness decreased.