Since the 19th century the term heat treatment has
meant a set of operations carried out on metal parts, comprising heating
followed by soaking at steady temperature, then more or less rapid cooling to
the ambient temperature. The parameters (time, temperature, etc.) vary
according to the temperatures
at which the material structure is modified.
The monitoring curves can easily be shown by a
The purpose of heat treatments is to give the steel
particular properties suited to its implementation or use. Heat treatments can
be classified into two types of treatment: balanced treatments, including homogenisation
annealing, and unbalanced treatments, including
effects of heat treatments are varied and enable
steel characteristics and properties to be modified.