Cryo treatment -- does it do what it says? Or snake oil?

[phonix]

"In Cryogenic treatment the material is subject to deep freeze temperatures of as low as -185°C (-301°F), but usually -75°C (-103°F) is sufficient. The Austenite is unstable at this temperature, and the whole structures becomes Martensite. This is the reason to use Cryogenic treatment."

Is this true? Does it increase the tensile properties of steel? Where can I read independent lab testing on this rather than propaganda from a vendor?

This is pretty funny stuff:

http://www.vhaudio.com/cryo.html

From a subjective standpoint, common evaluations of cryoed vs. non-cryoed parts are:

Wider dynamic range
Smoother, more refined highs
Better bass articulation
More organic presentation
Deeper, more three dimensional soundstage

 

[mewhg]

We cold treat our alloy parts and it does give an increase in wear resistance. I had a carburized part that I could not get above 56-58RC with a decent temper. After cold treating with the same temper the part was 64RC.

 

[kenvlach]

phonix,
The subzero treatment to convert retained austenite (that fraction of austenite which didn't transform during quenching from the high, austenitizing temperature) into martensite is well-known. It is somewhat conceptually easy to understand: A diffusionless transformation (so not requiring atomic diffusion) with a volumetric change. So, the cooling contraction stress can flex the austenite lattice into martensite.
I checked my ASM Heat Treatment handbooks: the same subzero cooling treatment for 440C martensitic stainless is given in the 8th Edn. (1964) as well as the newer ones.

Seaarch for past threads, e.g., thread330-112765
Some publications by a Louisiana State Univ. Professor:

http://www.nitrofreeze.com/datasheets.html

A brief paper by the EPRI:

http://www.energy.ca.gov/process/pubs/cryog_processing_tc113571.pdf

A few more papers, some definitely scientific:

http://www.nitrofreeze.com/news.html

 

[SnTMan]

phonix, any serious audio buff will be interested in this:

http://www.referenceaudiomods.com/M...OB_C37_C&Category_Code=VOLUME&Product_Count=2

and perhaps this:

http://www.referenceaudiomods.com/M...OB_C37_C&Category_Code=VOLUME&Product_Count=2

Regards,

Mike

 

[davefitz]

are you implying that there is something wrong with snake oil?

 

[tomwalz]

What we have seen is that it works but not reliably predictably.

We are in tools, especially tools used in multiples. Having some tools work a lot better and some work a little better doesn’t do us any good.

If I substitute one grade of carbide for another I can be about 90% sure I will double tool life in a given material. As far as I know there is no way to predict that a certain kind of cryogenic treating applied to a certain kind of material will give a predictable change in results.

Tom


Thomas J. Walz
Carbide Processors, Inc.

http://www.carbideprocessors.com

 

[NickE]

As a Live Sound engineer, and also as a metallurgist. I find that claims of cryo treatment as a method to improve audio interconnects as complete hogwash.

With no activation of a structure change there is going to be no change in electrical or frequency, time based signal transfer.

nick

 

[EdStainless]

There is a second effect that is related to the conversion of retained austenite, that is improvements in carbide morphology. For highly alloyed grades that tend to suffer from retained austenite and/or have high amounts of certian types of carbides (that I can't remember now).
Often this lets you work at higher hardness with the same toughness, or hold the hardness and get more toughness.

The snake oil part is that cryo doesn't help all alloys, and some it doesn't help much.

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Rust never sleeps
Neither should your protection

http://www.trent-tube.com/contact/Tech_Assist.cfm

 

[SnTMan]

davefitz, nothing WRONG with snake oil, as long as that is what a person wants to buy

Regards,

Mike