(1. 上海交通大学 上海市激光制造与材料改性重点实验室，上海 200240；
2. 宝山钢铁股份有限公司 研究院，上海 201900；
3. 汽车用钢开发与应用技术国家重点实验室（宝钢），上海 201900；
4. 高新船舶与深海开发装备协同创新中心，上海 200240)
摘 要: 光纤激光因其波长短、材料吸收率高的特点，在高反射材料焊接中具有广阔的应用。采用光纤激光实现6016铝合金薄板的焊接，并通过人工时效处理提高焊接接头的力学性能。结果表明：(180 ℃, 10 h)人工时效处理工艺可以将焊缝中心硬度由67 HV提高到84 HV，焊接接头拉伸强度由185 MPa提高到274 MPa。6016铝合金接头在α(Al)基体中析出大量纳米尺度的β强化相，促使接头力学性能提高。但是，接头焊缝区快速凝固组织特性会影响时效强化效果，导致焊缝区力学性能的提高效果要低于母材。
关键字: 6016铝合金；光纤激光焊接；力学性能；时效；强化相
（1. Shanghai Key Laboratory of Materials Laser Processing and Modification, Shanghai Jiao Tong University, Shanghai 200240, China;
2. Research Institute, Baoshan Iron & Steel Co., Ltd., Shanghai 201900, China;
3. State Key Laboratory of Development and Application Technology of Automotive Steels, Shanghai 201900, China;
4. Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240, China）
Abstract:The fiber laser is widely used in the welding process of the high-reflectivity material for its short wavelength and resultant high absorptivity to those materials. The fiber laser welding was applied to join 6016 aluminum sheets and a postal aging treatment was employed to improve the mechanical properties of the joint. The research results show that the aging treatment of (180 ℃, 10 h) increases the hardness of the joint from 67 HV to 84 HV, and tensile strength from 185 MPa to 274 MPa. The microstructural observation shows the a large number of β″ strengthening phase particles in nano-scale size precipitate from α(Al) phase and improves the mechanical property of the joint. However, the rapid solidification microstructure in the fusion zone has a negative influence on the strengthening of aging treatment. The increase degree of mechanical property in fusion zone is lower than that in base metal zone.
Key words: 6016 aluminum alloys; fiber laser welding; mechanical properties; aging process; strengthening phase
