Quenching and tempering involves a combined heat treatment procedure of hardening and subsequent tempering.
A particular feature of quenching and tempering is that tempering takes place at high temperatures of up to 700 °C. Tempering of martensite forcibly expels part of the dissolved carbon. With increasing tempering temperature, tensile strength, yield strengths and hardness are reduced, whereas elongation, constriction and notched impact strength increase.
One refers to quenching and tempering similarly to hardening, depending on which quenching medium is used for hardening, i.e. water, oil or air quenching and tempering
Quenching and tempering is particularly useful for workpieces that are subject to dynamic loading and from which high ductility is expected. Quenched and tempered steels have a wide spectrum of applications due to their good strengths with high ductility at the same time, all heat-treatable steels are suitable.
Benefits of quenching and tempering
- Good notched impact strength
- High strength with high ductility at the same time
- Good flexural strength