Basque Research, Spain, has been developing cryogenic treatments for steel in a program that has the goal of understanding both the microstructural changes and the mechanisms that cause them when steel is cooled to cryogenic temperatures below −153°C. One process currently being explored is a multi-phase cryogenic treatment based on the repetition of short, fast, cryogenic cycles.
It allows processing time to be considerably reduced, which enables energy consumption and costs to be cut. The results achieved with this type of process are said to be better than those achieved by conventional cryogenic treatments. Researchers are also exploring the application of cryogenic treatment between hardening and tempering.
Conventional cryogenic treatment consists of slowly cooling the material to about −180 ºC, keeping it at that temperature for a long period of time, and then reheating it to ambient temperature. The fact that it takes so long is a clear problem.
