Surface hardening process

Heat treatment is largely divided into the entire heat treatment and surface heat treatment. The entire heat treatment helps improve the entire nature of a material through heating and cooling, including bright one, vacuum one, and salt bath one. And, the methods of the entire heat treatment include normalizing, annealing, quenching, and tempering. The surface heat treatment helps improving the nature of a material through heat treatment of only the material's surface, including carburizing, nitriding, induction hardening, and flame hardening.