ABSTRACT

NiTi thin sheets were ultrasonic spot welded with a Cu interlayer, where different welding vibration amplitudes were applied to study the influence on the surface and interface microstructural characteristics, phase transformation behavior and mechanical response of the joints, which aimed to enhance the joint performance by proper optimization of the process parameters. An excellent bonding interface was achieved when an optimized vibration amplitude was applied, with a recrystallized microstructure formed in the Cu foil side near the bonding interface, which helped to improve the mechanical performance of the joints. Joints made with vibration amplitude of 55 μm had an improved strength compared to the NiTi base material.

摘要

NiTi薄板采用Cu夹层进行超声点焊，在其中应用不同的焊接振动幅度来研究其对接头表面和界面微观结构特征，相变行为和机械响应的影响，旨在通过适当的方式提高接头性能。工艺参数的优化。当施加最佳的振动幅度时，可获得优异的粘合界面，并且在靠近粘合界面的Cu箔侧形成了再结晶的微观结构，这有助于改善接头的机械性能。与NiTi基材相比，振动幅度为55μm的接头具有更高的强度。