Interfacial characteristics of Ti/Al joint by vaporizing foil actuator welding

The 3003 aluminum alloy was welded to the pure titanium by a collision welding method called as vaporizing foil actuator welding (VFAW). By designing a groove die with special angles, it was found that the interfacial wave morphology transformed from irregular to regular, and recovered to irregular with increasing the angle. The best impact angle range was from 16°to 24° to generate the regular interfacial wave. By building the VFAW experiments with parallel standoff gaps, influence of standoff and input energy on interfacial morphology and mechanical properties were investigated. To generate obvious interfacial wave, the standoff was higher than 0.93 mm at constant input energy of 6.4 kJ, and the input energy was from 6.4 kJ to 8.0 kJ at constant standoff of 0.93 mm. A small amount of intermetallic compounds only appeared at troughs of the wavy interfaces with the maximum size of 3–6 μm. The interface has higher strength than the aluminum base metal in the range of the optimized processing parameters. The influence of the collision angle on the interfacial wave was clarified from the view of fluid dynamics. The relationship between the mechanical properties and the interfacial wave was discussed based on the impact velocity measured by a photonic Doppler velocimetry (PDV) method.