[DG624]

It is always good to have an objective view. I originally read about this in GRMotorsports in an ad. I then looked it up and the web site described their "Cryo" processing and its benefits:

"Residual stresses exist in all types of parts from engines to tooling. The stress is introduced into the part at the time of casting, forging, heat treating or machining. These stresses create an invisible random grain pattern. Parts expand from the heat generated during operation, the retained stresses cause uneven expansion which results in increased dimensional instability with increased wear and decreased performance.

Deep Cryogenic temperatures are required to effect a complete molecular change in most alloys giving the microstructure a more uniform grain structure. Deep Cryogenic temperatures distribute large quantities of very hard, fine carbides, that develop uniformly throughout the structure.

Heat treatment of steel involves the transformation from its softer more malleable annealed state to a harder more durable state. This is done, as it has been for centuries, by heating the steel and then rapidly cooling it. The result is a harder and more wear resistant object. The metallurgical reason for this is that as the steel is heated, it forms an austenite (large, unstable particles of carbon carbide) crystal structure or matrix. Rapidly cooling or quenching the steel (traditionally at room temperature) triggers some of the austenite structure to change into a different matrix called martensite (a more uniformly refined grain structure). It is the martensite structure that gives tempered steel its hardness and wear resistance for applications from cutting tools to engine parts.

The goal of heat treatment is to transform as much of the austenite as possible into martensite. However, some of the austenite is retained even after tempering. Through experimentation it was found that if the quench was lower than the traditional room temperature, less austenite was retained. Cryogenic treatment is an extension of the well known heat and quench cycle. Cryogenic Processing is specifically about controlled thermal cycling of materials over a period of up to 72 hours.

The austenite to martensite transformation achieved by deep thermal cryogenics is responsible for the exceptional wear characteristics due to a denser structure and resulting in a larger surface area of contact wiich reduces stress, fatigue, friction, heat and wear.

Cryogenic processing is a one time process, not a coating or surface treatment that can be machined away. It will not make the component more brittle or change its physical size."

SOunds like it is all good, except for the cost which is still not high. If the metal is all the same then maybe it would be good but what about gears that are supposed to be hard already?

The other part of the process is the polishing and that is described as:

"The REM (R) procedure is not a polishing process but rather a finishing process. REM (R) is a chemically excellerated process which involves two steps. The first step, referred to as the "Refinement Process", involves a chemical interaction on the surface of the part. A soft, thin (one micron) film is formed on the surface of the part. The part then interacts with the ceramic media in a special vibratory bowl.

During this interaction the film is physically removed from the "peaks" of the processed part and the "valleys" are unaffected. The chemically induced film re-form only at the peaks that are interacting with the vibratory media, and the process repeats itself. Over time, the peaks are removed, leaving only the valleys, producing the improved micro finish. The second step is referred to as the "Burnish Process." After the required micro finish is achieved, a mild alkaline mixture is introduced. After a relatively short period a polished, chrome-like finish is produced. In addition to the polishing effects, this step effectively removes all traces of the film formation from the "refinement" process.

BENEFITS
Reduced Friction, Vibration & Noise
Improved Shifting
Longer Life of parts
Reduction in Lubricant Temperatures Reduction in metal to metal pitting

APPLICATIONS
Gears of all types
Cam Shafts
Crank Shafts
Rocker Arms
Transmission Gears