- Abstract.The microstructural features of the bonding zone in magnetic pulse welds of similar and dissimilar metal pairs have been investigated. The nature of the reactions and phase formation that occur in the magnetic pulse joints displaying a discontinuous pocket type or a continuous transition layer along the bond interface is explained in terms of local melting followed by rapid solidification. The most significant feature of the transition zone created during the magnetic pulse welding process is the hardness increase of the interface layer. For similar base metals the main cause of the hardness increase is the fine grained microstructure created during the rapid local solidification. In the dissimilar base metal welds the increase in hardness is a result of the formation of stable or metastable intermetallic phases and of the fine grained microstructure of the bonding zone.