Magnetic Pulse Welding for Dissimilar and Similar Materials

Abstract

The Magnetic Pulse Welding (MPW) process, a cold solid state welding process, is an industrial process, operating at several high volume manufacturing facilities. MPW is accomplished by the magnetically driven, high velocity, oblique angle, impact of two metal surfaces. At impact, the surfaces (which will always have some level of oxidation) are stripped off and ejected by the closing angle of impact. The surfaces which are then metallurgically pure, are pressed into intimate contact by the magnetic pressure, allowing valence electron sharing and atomic-level bonding. This process has been demonstrated in the joining of tubular configurations of a variety of metals and alloys [1],[2],[3]. Product designers are frequently constrained by the restrictions of traditional joining technologies, which place certain limitations on the type of joint, the materials that can be joined and the quality of the joint. Solid state welding allows manufacturers to significantly improve their product designs and production results by enabling both dissimilar and similar materials to be welded together, thus providing the opportunity to use lighter and stronger material combinations. Magnetic pulse welding is a fast, noncontact and clean solid state welding process. A review of the main elements of the process is presented here along with typical quality testing results and some applications.