ABSTRACT
Steel is the most complicated alloy, in terms of the interplay between alloying elements, processing, microstructure and properties. This chapter presents the phases in steels and the associated Fe–C phase diagram. It discusses the effect of alloying elements on phase stability. The core of the chapter concerns the phase transformations in steels, which take place under isothermal and continuous cooling conditions and shape the microstructure of steel. It then discusses the development of desirable microstructures and properties through heat treatment. The chapter also presents several case studies, regarding the interplay between processing, microstructure and processing. It explains the phase transformations in steels. Steels exhibit a vast diversity of microstructures and mechanical properties. Steel strength ranges between 200MPa and 5GPa. Steel is the most complicated alloy, in terms of the interplay between alloying elements, processing, microstructure and properties. The various phases, which form in steels, are responsible for the large range of properties.
