Experimental Investigation of Spot Welding Process on Metallic Targets Impacted by Flat and Conical Projectiles

Due to the ability of the spot-welding process to create a quality connection between metal plates, especially those with very different mechanical properties, this process has been taken into consideration in recent years. In this method, when two metallic plates welded together under high applied pressure, an atomic bonding is created at the surface of the plates. A single stage compressed gas gun impact test facility was used for carrying out Impact Spot Welding tests. In this study the steel plate with a thickness of 4 mm was considered as a base plate and copper, brass, and aluminum plates were used as front layers and they are under direct contact with flat- and conical-nosed metallic projectiles within the velocity ranging from 100 to 150 m/s. In order to investigate the effect of various parameters in this process, different combination of bilayer metals with 0.1, 0.2 and 0.5 mm gaps were used. The welded interface was studied by Scanning Electron Microscopy (SEM). The results of this study showed that in the collision zone, especially in the central areas a complete bonding has occurred.