مجموعة أبحاث وملفات عن المعالجة الحرارية للصلب
Steel Heat Treatment
Heat Treatment of Steels
Heat Treating is the process of heating and cooling a steel to obtain desired properties.
Various types of heat treatment processes are used to change the following properties or conditions
of the steel:
– Improve the toughness – Improve the machinability
– Increase the hardness – Refine the grain structure
– Increase the ductility – Remove the residual stresses
– Improve the wear resistance
– The process of cooling austenite very rapidly or at a controlled rate to achieve a desired
* The rapid cooling suppresses the formation of austenite to α + Fe3C
– Quenching of austenite produces martensite, which is used for applications that demand a hard
material (e.g. knives, razor blades, surgery tools, cutting tools, etc).
* When austenite + ferrite is quenched, all of the austenite transforms completely to
martensite while the ferrite remains unchanged.
* When austenite + cementite is quenched, again all of the austenite completely transforms
into martensite while the cementite remains unchanged