Comprehensive Weldability Criterion for Magnetic Pulse Welding of Dissimilar Materials

Abstract

Despite its exceptional ability to join dissimilar materials and environmental friendliness, several challenges must be addressed in magnetic pulse welding (MPW). The conventional weldability criterion (i.e., minimum impact velocity) is analytically calculated as a function of material properties without considering the geometry of electromagnetic coil, electrical and physical parameters, making the minimum impact velocity a necessary but not sufficient condition for a sound MPW joint. A new weldability criterion, namely effective impact velocity, is proposed, which overcomes the conventional weldability criterion’s limitations. The effective impact velocity can be inversely modelled to identify shop-floor relevant process parameters and it eliminates the need to fabricate several coils in the process and product proving stages. The proposed approach is demonstrated by a case study on tubular welding of Aluminium and SS304. The weld’s soundness produced with computed process parameters was corroborated by experimental observations on lap shear tests, hardness measurements, optical and scanning electron microscopy, and surface energy dispersive spectroscopy mapping. This investigation is expected to pave the way for developing the process window for MPW of several material combinations, with high cost and time savings.