ABSTRACT
This chapter examines the study of the metallurgical aspects, design approaches, the selection of process parameters, equipment specifications, and physical phenomena that are imperative to understand the manufacturing and operation of induction heat treating (IHT) machinery. Physical metallurgy deals with the physical, chemical, and mechanical characteristics of metals, various intermetallic compounds, and mixtures referred to as alloys. The chapter provides a simplified introduction regarding the structure of metallic materials and critical temperatures. It discusses the effects of the most commonly used chemical elements in steel. Steels with carbon content below approximately 0.77" belong to the group of hypoeutectoid steels. The isothermal transformation (IT) diagram helps develop some ideas regarding the formation of the post–heat-treating microstructures based on the specifics of cooling. Spray quenching is the most popular quench method used in induction hardening. There are several metallurgical and microstructural phenomena associated with excessive temperatures. This includes severe grain coarsening, scaling, intergranular oxidation, grain boundary liquation, and others.
