自然时效对铝/钛超声波焊接接头的影响

Effect of Natural Aging on Al/Ti Joints Obtained by Ultrasonic Welding

对6061-O Al合金和Ti6Al4V合金异种金属进行超声波焊接,分析焊后30min和自然时效8个月2种情况下接头的维氏硬度、最大拉伸载荷和断裂能,研究自然时效对接头力学性能的影响.结果表明:经自然时效后,接头铝侧的硬度得以提升,硬度分布由"W"形转变为倒"U"形;自然时效可以显著增大接头的最大拉伸载荷,并使其断裂模式由"纽扣"模式转变为"界面"模式;然而,接头的断裂能在自然时效之后反而降低.因此,自然时效可以有效提高铝/钛异种金属超声波焊接接头的力学性能.

In order to study the effect of natural aging on the mechanical properties of the joints, ultrasonic welding of 6061-O Al and Ti6A14V alloys were conducted, and the Vickers characteristic hardness, peak load and fracture energy of the joints, within both 30 rain of welding and after 8 months of natural aging was investigated. The results show that the hardness of the side of aluminum alloy in the joints was enhanced, after the natural aging treatment, with the distribution of the hardness changed from the ＂W＂ shape to the ＂inverted U＂ shape. The natural aging treatment can significantly improve the peak load of the joints. However, the fracture energy of naturally aged joints is decreased. Therefore, it can be con- coulded that natural aging can effectively improve the mechanical properties of the Al/Ti joints obtained by ultrasonic welding.