First commercialized in the 1960s, the cryogenic process has had a major impact by offering exceptional benefits to metal parts that are used in a wide range of industries.
When it comes to properly maintaining tools, extending the life of parts, and achieving maximum efficiency, the cryogenic process cannot be understated. These higher-quality, longer-lasting products and parts lead to lower costs and more value for businesses and customers alike.
Let’s start with the basics.
What is the Cryogenic Process?
The cryogenic process is the treatment of steel or other metals through very low temperatures in an effort to increase wear resistance and remove residual stresses by enhancing the transformation of the softer austenite iron to the harder, tougher martensite structure.
According to ASM International, “common practice identifies –84 °C (–120 °F) as the optimal temperature for cold treatment. There is evidence, however, that cryogenic treatment of steel (also referred to as deep cryogenic treatment, or DCT), in which material is brought to a temperature on the order of –184 °C (–300 °F), improves certain properties beyond the improvement attained at cold treatment temperatures.”
In short, cryogenic treatment uses extreme cold to enhance the characteristics of and to modify the performance of materials.
This cold treatment of metal via the cryogenic process is far superior to that of heat treatment alone. Whereas heat treatment requires the temperature to be controlled at a precise level to avoid reversal of the austenite-to-martensite transformation, cold treatment only requires extreme low temperature reduction.
Benefits of cryogenic treatment
To start, cryogenic treatment considerably extends tool life.
According to a published paper by IOP Science, “tool life is improved considerably by 92% after cryogenic treatment.” Similarly, an article from Anna University says their study “found that cryogenic treatment imparts nearly 110% improvement in tool life.”
And roughly doubling the life of tools accounts for a significant reduction in costs:
- Tooling costs are reduced because having stronger, sturdier tools means you’ll be able to increase the time between replacing tools
- Replacement costs are reduced
- Labor costs are reduced because less time and manpower are required to replace tooling
More specifically, stress relief is a vital benefit of the cryogenic process. Under normal conditions, residual stresses resulting from high temperature heat treat changes are a common contributor to tool failure.
However, the introduction of cryogenic treatment reduces these stresses by refining the microstructure of a metal, balancing the expansion of the inner core and stabilizing all layers of the metal.
All in all, cryogenically treated tools provide substantial value thanks to the cost-reduction benefits of roughly doubling tool life, removing residual stresses, and eliminating downtime.