What are the types and benefits of Knife Heat Treatment?
When it comes to choosing an appropriate substrate material for your machine knife you need to carefully consider the heat treatment processing requirements to ensure that you are obtaining the optimum performance properties from the steel used to manufacture the machine blade. Here at Precision Edge we provide our own knife heat treatment service so our customers can be sure that their blade is of the highest quality.
There are generally three main treatments offered as part of blade heat treating services: heating and tempering, austempering and martempering. These treatments help to increase the life of the blade and improve its ability to resist wear and tear – especially important for sliding/rolling knives within a machine. But what characterises each of these treatments? Here is an explanation of the three treatments offered as part of a heat treatment service and the benefits they can offer:
Hardening and tempering
Hardening and tempering is the most common knife heat treatment, a three-stage process designed to give components the mechanical properties they need for their intended service. In this process, the knife is subjected to controlled heating to an extremely high temperature (usually around 800-900°C) before being rapidly cooled or ‘quenched’ in oil or water. The knife is then ‘tempered’ or soaked at a lower temperature to relieve stress on the blade.
Hardening and tempering can be carried out in ‘open’ conditions, such as in furnaces, or in a protective environment such as a gaseous atmosphere or vacuum if the surface of the knife must be kept clean. This variation is known as ‘neutral’ or ‘clean’ hardening.
Martempering
Martempering is a specialised quenching option for steel components containing certain alloys or of certain sizes. This uses a higher temperature quench than normal tempering, such as in molten salt or hot oil, with the aim of reducing distortion of the knife.
Austempering
Like mastempering, austempering is a specialised quench suitable for applying to thinner knives made of certain high-carbon steels or thicker steel knives containing certain alloys. This also requires a high temperature quench, usually in molten salt. This again helps reduce distortion of the knife while also giving it a tough structure that requires no further tempering. /p>
What are the benefits?
Making use of a heat treatment service like hardening and tempering will help to give your knives extra strength and durability, potentially saving on the expense of further knives. Neutral cleaned hardening particularly helps knives to keep their surface integrity – great for machine knives working with food or other sensitive material.
Contact us
Here at Precision Edge we offer a highly accurate and consistent knife heat treatment service offering all of the above heat coatings. We can also guarantee full traceability with our in-house quality assurance control system. If you are interested in taking us up on our blade heat treating service, please don’t hesitate to contact us here at Precision Edge or speak to us now on 01403 892510. We’d be delighted to be of service!
