Induction Heating in Sustainable Manufacturing and Material Processing Technologies – A State of the Art Literature Review

Abstract

Induction heating is a fast, energy efficient and environment-friendly process with almost zero emission to the environment. The present work aims at astuteness to the role of induction heating for sustainable material processing technologies like casting, welding, joining, heat treatment, surface modification, processing of bio-oils and numerous other applications. The objective is to provide an overview of the induction heating process used in different manufacturing technologies. Induction heating is a complex combination of the creation of an electromagnetic field, eddy current formation and heat generation, heat transfer and corresponding metallurgical changes of the substrate material. The utmost interest of the present article is to describe the phenomena of heat generation in different applications of induction heating process and the parameters that influence the manufacturing processes (coil current, power, frequency, holding force, holding time and no of turns in the coil, effects of impeder etc.,) as well as the inhibitor that affects the thermal energy distribution of the process (skin and proximity effect). The induced heating process uses a high-frequency alternating current to generate eddy current in the work part leading to Joule’s heating, aided by adequate fixture for heating or melting. If the part is magnetic in nature, then additional heating through hysteresis loss is obtained until the Curie temperature of the material. Skin effect supports the current flow on the surface and proximity effect attracts the work-part towards each other by an opposite magnetic field. Induction heating is considered for sustainable material processing, as there are no emissions as well as a non-contact process where heat is generated inside the body and does not behave like an application of external heat source. Therefore, such a heat source has huge potential in upcoming research field to develop sustainable and environment-friendly material processing technologies.