Analysis of electromagnetic welding process for thin similar and dissimilar metallic strips

Abstract

Electromagnetic Welding (EMW) is an impact welding process and hence it is characteristically different than the other conventional fusion welding processes. It offers many distinct advantages, provided it is used, taking into account its limitations. In the field of conventional welding, there are mainly two challenging propositions, namely i) welding of aluminium and ii) welding of dissimilar metals. The welding of aluminium is difficult due to its oxidation and welding of dissimilar metals is the cause of concern due to difference in their melting points. The use of aluminium and its alloys, which are light weight metals, is going to increase in future (especially in automobile and aerospace industries). There will be many applications in which welding of aluminium will be required with other metallic parts. Similarly, the welding of metals like copper, Stainless Steel (abbreviated as S.S. hereafter) etc is required for the fabrication of components in various engineering industries. Considering this scenario, the analysis of EMW process newlinefor Al, Cu and S.S. with similar and dissimilar combinations, is undertaken in the present work. In contrast to the aforementioned difficulties, aluminium is the easiest to weld electromagnetically. EMW offers solution to some of the problems mentioned above owing to the fact that the welding is achieved by impact and the melting point and other thermal properties do not of much significant role. The processes like surface preparations, storing in inert atmosphere etc could be eliminated in EMW operation. Apart from this, EMW has many other advantages such as high production rate, reproducibility, automation ease, no need of preparatory methods etc. This warrants serious consideration for harnessing its potential. On the other hand, there are some limitations of the EMW process, which include-1) It is less efficient for metals with low electrical conductivity and 2) It is not suitable for large size jobs (exceeding about 1 meter).