摘要
采用搅拌摩擦焊对6mm厚汽车用2219铝合金进行焊接，研究了其焊接接头的组织与性能，并对其焊接过程进行了数值模拟。结果表明，焊核区的晶粒形态为细密微小的等轴晶，热机影响区的晶粒发生了较大的弯曲和变形，热影响区的微观组织粗大；T1沉淀相在热机影响区和热影响区内发生溶解并粗化，热机影响区的位错结构比焊核区和热影响区较为密集；焊接接头的硬度呈”W”形分布，焊核区和热机影响区的整体硬度范围在51～66HV．热机影响区与热影响区的过渡区域的硬度值最低，为51HV；纵向残余应力的分布是明显的双峰特征．在靠近焊缝中心线的附沂丰萼表瑚为柿廊力爵大佰存执影响庆的沩缘为147MPa。
2219 aluminum alloy with thickness of 6 mm was welded by friction stir welding. The microstructure and hardness were studied. The welding process was simulated. The results show that the microstructure of nugget zone is tiny grain of fine equiaxed, and the grains of thermo-mechanically affected zone are greatly bending and deformation while the grains of heat-affected zone is thick and large. T1 precipitates in the heat-affected zone and thermo-mechanically affected zone were dissolved and coarsening occurs. The dislocation structure ofthermo-mechanically affected zone is more intensive than the heat-affected zone. The distribution of the welded joints hardness is ＂W＂-shaped. The hardness of weld nugget area and the thermo-mechanically affected zone ranges is 51-66 HV, the minimum hardness is in the transition region of heat-affected zone and thermo-mechanically affected zone is 51 HV. The distribution of longitudinal residual stress is bimodal characteristics evident while in the near vicinity of the weld centerline is mainly for tensile stress. The maximum value at the edge of the heat-affected zone is 147 MPa.
出处
《热加工工艺》
CSCD
北大核心
2014年第3期196-198,共3页
Hot Working Technology
关键词
铝合金
搅拌摩擦焊
微观组织
硬度
数值模拟
aluminum alloy
friction stir welding
microstructure
hardness
numerical simulation
