Søren wrote:
Anyway, could you explain why it works?
I have, by the way, reviewed a couple of my text books on the subject, but came up empty.
Metals and plastics are formed in a state of stress. The article is in an inherent state of tension do to the process of manufacture.
Cryogenically freezing plastics (some) and metals, as close to absolute zero as possible (since we are, obviously, unable to achieve absolute zero) you put the article as close to a zero motion molecular state of mass as possible. Just as with most elements the lower the temperature, the harder the material because the molecules are more dense. In metallurgy this is referred to as thermal compression. By exposing the item to prolonged situations of high density thermal compression, when the article is returned to a normal temperature, the molecules return in a more unified pattern (although tests show that the overall density of the material remains higher even after it returns to room temperature). This increased density following the process is a result of carbide fillers imparting themselves into the metal. This pattern is very different from the stressed molecular pattern inherent with plastic and metal manufacture. (this process is explicitly defined in the 1987 "Batelle Report")
Another change occurs because carbon carbides are precipitated from cryogenic treatment (they intertwine in a tight 5 sided structure). This imparts greater resistance to wear.
Resulting density and hardness tests are easily observed on the Rockwell Hardness scale. Overall density, hardness, and molecular tension have a direct correllation with acoustics of the item.
**Rick Denney type disclaimer**
(who doesn't claim to be a metallurgist, molecular chemist, solid state phys... or anything close)