Impact Welding in a Variety of Geometric Configurations

Abstract

Magnetic pulse welding is an electromagnetically assisted high strain rate impact welding technology. The physical principle is similar to explosive welding and it also belongs to solid state impact welding. This high velocity oblique impact welding has been applied to various lap joint configurations. Three different geometric configurations on plate-to-plate welding were studied in this paper. They are direct lap joint, pre-flange lap joint, and lap joint with embedded wires. All of the three welding configurations have been used to provide metallurgical bonds between both similar and dissimilar metal pairs. The welded materials include copper alloy, aluminium alloy, and steels. The plates are centimeter or more thick and often centimeter in extent. The critical welding process parameters were instrumentally investigated by Rogowski Coil and Photon Doppler Velocimetry. Metallographic analysis of the welded interface showed refined grain structure. The mechanical properties of the welded plates were studied by lap shearing, peeling and nano-indentation tests. The test results showed that the impact welded interface has a much greater micro-hardness and fracture toughness than the base metals.