Vacuum Hardening

Vacuum hardening is the hardening of components under a controlled partial pressure, during which temperatures of up to 1300°c can be reached. The aim of this process variant is the creation of bright metallic workpiece surfaces which render further mechanical processing unnecessary.. 

the process

Hardening is the heating and subsequent cooling of steel at such a speed that there is a considerable increase in hardness, either on the surface or throughout. In the case of vacuum hardening, this process is carried out in a vacuum furnace in which temperatures of up to 1300°c can be reached. The quenching methods will differ with regards to the material treated but gas quenching using nitrogen is the most common, with argon used for special materials and oil for those which require faster quenching. We can offer all three of these mediums at our Letchworth facility.

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In most cases hardening takes place in conjunction with subsequent reheating, the tempering. Depending on the material, hardening improves the hardness and wear resistance or regulates the ratio of toughness to hardness.

commonly treated materials,
and fields of application

Practically all technically interesting steel alloys, such as spring steels, cold-worked steels, quenched and tempered steels, anti-friction bearing steels, hot-worked steels and tool steels, high speed steels as well as a large number of high-alloy stainless steels can be hardened.

Hardening of metals and steels in general is a very broad subject and there are many different routes which can be used for different materials. If you are in any doubt about the best process for your purpose, we would advise that speak to one of our experienced metallurgists prior to specifying treatments.

specialised vacuum hardening and vacuum treatments

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Aalberts Surface Technologies Heat Ltd | Disclaimer

Registered Address.: Aalberts Surface Technologies Heat Ltd, Blackhorse Road, Letchworth. SG6 1HD 

Tel: 01462 472147