Cryogenic Processing is the heat treating process of freezing metal to low temperature, to increase wear resistance and to reduce retained austenite after quenching.
Here's a link to a Discovery Channel episode on Cryogenics: Discovery Channel
Cryogenic Processing includes sub-cooling to -100F using liquid CO2, and sub-cooling to -300F using liquid N2.
Typical applications include tool steels, cutting tools, and high performance racing parts.
ThermoFusion offers cryogenic services in Northern California, as part of its heat treat and brazing service portfolio.
Cryogenic services include “sub zero” cooling, to facilitate precipitation hardening, and “cryo” treatments, at colder temperatures, to reduce retained austenite and increase hardness, toughness and wear resistance.
Examples of materials which benefit from sub-zero and cryogenic treatment include:
- Tool steels, for hardness
- Cutting tools, for edge hardness and wear resistance
- Engine blocks and cases, for wear resistance and toughness
- 8620 and 9310 gears, for hardness