Structural Steels

This chapter focuses on processing steels to attain a fine primary ferrite grain size to develop high strength. It first reviews the concepts and principles of recrystallization in plastically deformed metals. To examine how hot working can be used to control the austenite grain size, the chapter reviews the concepts of annealing of cold worked metals. It then looks at hot working and the grain size associated with it. Additionally, the chapter reviews the methods of strengthening in the steels that rely mainly on reduction in the primary ferrite grain size. It discusses basic methods used to develop a small austenite grain size, and hence a small primary ferrite grain size. Then, the chapter covers the processes involved in the precipitation hardening of the ferrite. Finally, it examines some commercial thermomechanical processes used on structural steels, namely hot deformation and controlled cooling.