There are three major steps of heat treating performed by a custom knifemaker or a factory, and an optional fourth:
- Austenitizing – heating the steel up hot and soaking
- Quenching – Rapidly cooling the steel
- Tempering – reheating the steel to a lower temperature such as 400°F (200°C) for 1-2 hours. This is typically performed 2-3 times (cooled to room temperature in between).
- Cryogenic or cold processing is an optional step that can be performed after the quench or in between tempering steps. It involves cooling the steel to as low a temperature as possible.
Fundamentally these steps can be performed with a wide range of equipment, and that equipment can have an effect on the results. Below I have written about some of the basic equipment setups.
Larrin is always a good read. I have really appreciated his help with my Crucible articles.
Read the whole thing at KnifeSteelNerds.com
Watch the video here…