This chapter describes surface modification processes that go beyond conventional heat treatments, including plasma nitriding, plasma carburizing, low-pressure carburizing, ion implantation, physical and chemical vapor deposition, salt bath coating, and transformation hardening via high-energy laser and electron beams. The chapter compares methods and includes several example applications.

This chapter discusses the process characteristics, advantages, disadvantages, and applications of various processes involved in surface hardening of steel. These include pack carburizing, liquid carburizing, gas carburizing, vacuum carburizing, plasma carburizing, gas nitriding, liquid nitriding, carbonitriding, and hardfacing. The chapter describes two surface hardening processes by localized heat treatment: flame hardening and induction hardening. It also briefly summarizes other surface hardening processes, namely, aluminizing, siliconizing, chromizing, titanium carbide coatings, and boronizing.