Heat treatment and surface engineering are seen as critical elements in the design and manufacture of strategic components in a wide range of market sectors and industries including air, sea and land transportation, energy production, mining, defense or agriculture. Heat treating is a group of industrial and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is metallurgical. Heat treatments are also used in the manufacture of many other materials, such as glass. Heat treatment involves the use of heating or chilling, normally to extreme temperatures, to achieve a desired result such as hardening or softening of a material. Heat treatment techniques include annealing, case hardening, precipitation strengthening, tempering, normalising and quenching. It is noteworthy that while the term heat treatment applies only to processes where the heating and cooling are done for the specific purpose of altering properties intentionally, heating and cooling often occur incidentally during other manufacturing processes such as hot forming or welding. This book deals a broad review of contemporary global developments in an application of thermal and thermochemical processing to modify the microstructure and properties of a wide range of engineering materials. A blend of conventional and novel applications, discovering a variety of processes employing heating, quenching and thermal diffusion, makes the book immense useful for a broad audience of researchers and engineers from academia and industry.