Frequently Asked Questions

1. Does the Cryogenic Process make the metal harder and therefore more brittle?

Although cryogenic processing makes metals (and other materials) more wear resistant, it rarely increases the hardness any significant amount. The wear resistance comes from a refined crystal structure and the transformation of retained Austenite into Martensite*, not an increase in hardness. Most items are post-tempered after cryogenic treatment to ensure they are not more brittle after processing.
*Dependant on material composition

2. Aren't hard coatings the best strategy for reducing metal wear?

A hard coating is a good strategy where light abrasion, friction, or light galling is a factor in wear. Hard coatings cannot strengthen metal, and if the metal underneath them succumbs to stress, abrasion, fatigue, or other wear factors, the coating will not protect it. We recommend cryogenic treatment to increase wear resistance in metals and alloys.

3. Cryogenic processing is easy, just put the part into liquid nitrogen.

You might get away with this 10% of the time. Successful cryogenic treatments involve bringing the part down in temperature at a controlled rate. Dropping the part into liquid nitrogen will expose the part to thermal shock. This could crack the surface or induce tensile residual stresses.

People have cracked engine blocks by pouring ambient temperature water into an over heated engine. 60 degree F water into a 300-degree engine block is only a 240-degree difference. A 60-degree F part dropped into liquid nitrogen represents a 375-degree difference.

4. We can't afford to put any more money into our tooling or product, even to make it better?

Our research has shown that the original cost of a tool is about 10% of the total cost of using the tool. It also shows that the greatest costs of using a tool are tooling failures and maintenance. Tooling failures and maintenance create down time, lost production time, delays and product failures. Cryogenically treating tooling parts can significantly improve the ROI (return on investment) of tools.

5. Does Cryogenic processing replace a heat treatment process or other existing treatments?

No, cryogenic treatment of metals and alloys it is an additional treatment to further improve what has already been done. The cryogenic process should always be applied after the high heat treatment has been completed. Post tempering of some items after cryogenic treatment uses a lower heat than that used in the metal hardening heat treatment process.

6. Can the extreme cold temperatures cause warping and dimensional changes?

It is very unusual for this to happen, but under certain circumstances, it can, such as when there is an inordinate amount of stresses in the steel, or if there is a large amount of retained austenite present. In both of these cases we are dealing with a poorly made sample.

7. How often do you have to re-apply the Cryogenic Process?

Never. The Cryogenic treatment is once only and is effective throughout the metal. Once the item has under gone cryogenic treatment, it will retain the benefits for the full life of the item. Generally blade edges demonstrate an increased in life of 100~300% after the Cryogenic treatment. The treated blade (or similar items) will give you the same benefits after being sharpened, time and time again.

8. Will it take special sharpening equipment to sharpen a blade that has been cryogenically processed?

As there is no significant increase in the Hardness of the item you will be able to sharpen the item exactly the same as you always have.

9. How long does the treatment take?

Once the item is in one of our treatment processors, it takes between 4 - 6 days, dependent on processor availability. You should allow up to 7 days turnaround time. If your request is urgent it may be possible to provide an immediate treatment time at the customers cost.

10. Will the Cryogenic treatment fix a problem with a poor heat treatment or an inferior metal?

No, it is not a cure all for poorly made tools and or components. A cheaply made tool will show little improvement from this treatment. However, the better the tool is to start with, the greater the improvement tends to be. Improvements in the life of quality metal components exposed to impact, abrasion, or heat can be up to 300%.

11. What materials can be processed?

SubZero Cryogenics Ltd has had success with ultra low temperature processing of metallic, ferrous and non-ferrous metals, carbide, alloy, carbon fibre, ceramic and plastic products.