本团队博士生杜飞等在Archives of Civil and Mechanical Engineering发表研究论文。

摘要：NiTi shape memory alloy (SMA) has been widely used in aerospace devices, and high velocity impact welding (HVIW) is one of the advantageous technologies for realizing NiTi SMA joining. However, in the traditional HVIW process, impact rebound leads to local interface failure to weld, which significantly reduces the service life and reliability of the joint. In this research, a new method by changing the local surface morphology of the target was introduced to the welding of NiTi and Al–Mg alloys. The interface microstructure and tensile shear strength of the joint were investigated, and the mechanism of local morphology reducing impact welding rebound was analyzed with smoothed particle hydrodynamics (SPH) simulation. The results show that the unwelded areas significantly reduced compared with traditional impact welding. Due to the introduction of impact angle, the kinetic energy of the flyer is converted more into interfacial plastic strain energy and thermal energy rather than elastic strain energy, which reduces the rebound and increases the overall strength. In particular, the spaced semicircle reduces more vertical rebound, resulting in the largest strengthening of 42.6%. This work provides a new path to improve the tensile shear strength of NiTi SMA welding parts.