What is the purpose of a heat treatment furnace ? 22 January 2024

Conseils

Why use a heat treatment furnace?

When you start making knives, you inevitably end up asking yourself the question of heat treatment. Heat treatment is essential to bring out the full potential of the steel used, whether carbon or stainless. Whether you're working with XC75 or MagnaCut, you won't get much out of it without heat treatment! The kiln heats the steel to a high temperature and then cools it instantly after heating, making the steel much harder than it was originally. This process must be carried out precisely for optimum results, hence the importance of the heat treatment kiln for heating and controlling the temperature of the steel according to its temperature curve, which can be consulted on its technical data sheet.

In practical terms, there are several tools available for heat-treating blades, but the idea is always the same: heat the steel quickly before cooling it just as quickly:

• The coal forge ;
• The gas forge;
• The electric furnace.

Which one to choose ?

There are a few criteria that will help you to better define your needs. Simply answer the following questions:

• Which temperature do I need ?
• How long should I heat my steel?
• What grade of steel do I work with?
• What is my budget?

To go into a little more detail, and to keep things brief: coal forging and gas forging should be reserved for carbon steels, which do not require excessively long holding times (one to two minutes per millimetre of thickness of the part, which is kind of a "general rule" even if there are some exceptions) or excessively strict temperature control: XC75, XC100, 90MCV8, 80Crv2, etc. A forge can easily achieve a correct austenitising temperature, but :

• Identifying the colour of the steel requires a trained eye;
• It is not possible to maintain a constant austenitising temperature with precision, which is a problem for stainless steels, as their resistance to corrosion is largely determined by the heat treatment.

And that's the whole point of an electric heat treatment furnace: it allows you to precisely reach and maintain a given temperature, to guarantee optimum heat treatment... and results to match! Focus on this tool, designed to make knifemakers' lives easier!

What is a heat treament kiln ?

A heat treament kiln is a tool used to heat your steel parts to a precise temperature for a specified holding time - to be adapted according to the steel grade you are using. Once the part has been heated, it's up to you to cool it quickly, whatever the medium: water (be careful, it's risky!), quenching oil, under aluminium plates with pulsated air... The idea is to bring the heated part back to room temperature as quickly as possible.

What are the advantages of using a heat treatment kiln ?

As mentioned above, quenching is a crucial stage in the treatment of your blades, which is why it's so important to equip yourself with quality tools that offer high precision and consistent heating quality. The main problem is that it is virtually impossible to maintain a consistently high and precise temperature for several minutes at the forge. Consequently, for stainless steels that need to be held above 1050°C, from 10 minutes for some to more than 30 minutes for those with a higher alloying element content, the use of a temperature-controlled heat treatment furnace is essential.

Let's face it, a heat treatment furnace is still an investment, but it's not a waste of money! Equipping a heat treatment furnace has nothing but advantages for the knife-maker's work :

• Suitable for all grades commonly used in knifemaking, both carbon and stainless steel;
• Maintains high temperatures accurately and consistently throughout the austenitisation phase;
• Ensure the repeatability of your heat treatments: when forging, you can tell the temperature by the colour, which can vary depending on the ambient light (for example). With a furnace, there's no problem: the programmed temperature is the one you'll heat to !

A heat treatment kiln with these characteristics is a formidable weapon for amateur knife-makers and professionals alike. The heat treatment of a blade is as critical as it is technical, which is why we have selected Prederi and their large range, a partner you can trust for quality.

Who is Prederi ?

If you're reading this, you're probably thinking about getting a heat treatment furnace... and that's just as well, because we're proud to distribute Prederi kilns ! The company offers products with unbeatable value for money for optimal heat-treatments... Their expertise dates back over sixty years, since the Italian company was founded in 1960! Prederi offers a wide range of heat treatment kilns for the knifemaking industry... but not only! Their range includes ;

• Heat treatment furnaces for knife makers
• Melting furnaces
• Muffle furnaces
• Chemical laboratory furnaces
• Chemical analysis furnaces
• Goldsmiths' furnaces

The success of this Italian company is based on its ability to understand and anticipate, with care and sensitivity, the most varied needs of its customers.

Expertise, experience, quality customer service, attention to the smallest detail and the use of top-quality materials have enabled the company to become a leader on the national and international markets.

Which heat treatment furnace should I choose?

Here is a table showing the different models of heat treatment and other furnaces and their technical characteristics offered by the company Prederi Vittorio & Figli and available for sale at Eurotechni. You will find the dimensions of the furnace in question as well as the maximum temperature it can reach and finally its price.

The larger the chamber, the greater the number of elements per series and/or the greater the size of the parts to be treated.

An important detail is that the heating time to reach maximum temperature is the same for all the models we offer, i.e. 20 to 25 minutes.

In addition to the undeniable technical quality of Prederi heat treatment furnaces, the company also offers a number of 'extras' that make all the difference:

• Each heat treatment furnace is carefully inspected and tested by Prederi before shipment.
• Your future heat treatment furnace is guaranteed for one year from the date of receipt.
• Prederi heat treatment furnaces are shipped FREE OF CHARGE throughout Europe.
• Each furnace is delivered with a test and compliance certificate and instructions for use.

A turnkey solution for ever higher quality heat treatment? Bingo. If you choose Prederi, you'll save time and money in the workshop.