HISTORY

For decades cryogenic processing was one of the best kept secrets in terms of metal processing.

Cryogenic processing is not a new technology. In fact, many historians date its use back to the times of ancient Swiss clockmakers who learned that if a material is stored in a cave for several years, during which it warms up in summer and cools down in winter, the properties of such material improve significantly.

It was during World War II that cryogenic processing was introduced into the armaments industry because better material properties were needed for war purposes. Parts were cooled down using the best available technology. Dry ice was put into cisterns with alcohol which made it possible to achieve temperatures of up to -73°C, thereby improving the material properties. At that time, several liquid nitrogen dipping trials were carried out in which a temperature of -184°C was achieved. Since the surface cooled down much faster than the centre, only a few pieces “survived” such a process. Therefore “deep cryogenic tempering”, as they called the process, was refrained from. After the war, other methods than liquid nitrogen dipping were tested such as part spraying or suspending just above the surface of the liquid nitrogen. All such methods were expensive and non-productive; the risk of instability and cracking still existed. Moreover, process control and repeatability were missing.

In 1966, Ed Busch established Cryo-Tech in the USA which made use of existing knowledge and became the first company to develop “dry” processing. Instead of dipping and spraying, they started to use dry steam LN2. This made it possible for them to manage the process temperature according to the type and cross-section of the processed material. A “basic process”, which was repeatable, was established on this basis.

During 1989, Peter Paulin, managing director of 300 Below, made contact with Busch and they together, after several years of trials, tests and computer technology implementations, developed a technology which served as a basis for 300 Below’s current software.