The term “Cryogenic Tempering” is used a lot in relationship to cryogenic processing. It is our opinion that cryogenic tempering is a term that is imprecise.
According to Metals Handbook, published by ASM, tempering is, “..reheating hardened steel to some temperature below the eutectoid temperature to decrease hardness and/or increase toughness.” (For more on ASM International, the world’s premier metallurgical society click here.)
Tempering used to mean hardening in archaic English, hence the persistence of phrases like “fine tempered steel” in advertising. This phrase is virtually meaningless. Any hardened steel would be tempered anyway. We feel it is confusing and inaccurate to use the word “Tempering” when referring to cryogenic processing.
Since the process rarely makes materials significantly harder (if it does, there was something very wrong with the heat treat), the term “Cryogenic Hardening” is also confusing, inaccurate, and does not convey the full impact of what cryogenic processing can do.
Cryogenic Stress Relieving
In the same light, the term “stress relieving” also indicates a specific process, and the use of cryogenics covers much more than stress relieving.
We call it Deep Cryogenic Treatment
“Deep Cryogenic Treatment” is a term that is currently being used by the scientific community to describe cryogenic treatment. It is used in most research projects done by colleges, universities and industry. As such it will probably become the dominant name of the process although anyone who is familiar with cryogenic science will know that -300ºF is not very deep into the cryogenic range, which starts at -244ºF according to the Cryogenic Society of America. Controlled Thermal Processing is currently experimenting with temperatures down to -450ºF, which is deep cryogenics, as it is very close to absolute zero.
Is it nit picking to criticize what people call the process? Maybe it is, but fancy sounding names often confuse the issue as to what the process does. We are tending to align ourselves with the scientific community in order to be concise.
One term that does not apply to what we do is Cryonics. The word Cryonics refers to the process of freezing living tissue. The objective is to bring it back to life in the future.
For more information on Deep Cryogenic Treatment click here.