Heat Treatment, what is it exactly?

The term heat treatment encompasses all processes that modify specific material characteristics through heating and cooling of the material.

Why are metallic materials heat treated?

Heat treatment can bring about targeted changes in the characteristics of metallic materials. Improvements in hardness, strength, workability and durability of materials can be achieved.  The cause of these improvements arises from changes in the structure of the material.

What happens when steel is heat treated?

The term „steel“ includes all iron alloys except cast iron.  To produce alloys other metals (e.g. chrome, nickel, tungsten) are added to iron, the most important alloying element in steel being carbon.

The importance of carbon in heat treatment becomes clear when one realises that steel with a carbon content of 0.1 % is almost impossible to harden and yet with a carbon content of 0.7 % the maximum possible hardness can be attained.

A knowledge of the iron-carbon phase diagram is a pre-requisite to understand all heat treatment processes. 

With help of the iron-carbon phase diagram it is possible to ascertain the state of a non-alloyed steel with a known carbon content at a specific temperature and, further, to determine the structural changes that will result from changes in temperature.

To the layman it appears that the heat treatment process is a relatively simple procedure, unfortunately this is not the case.  In fact, in course of a single heat treatment procedure more atoms are forced to change position than a in a whole day’s production within an active nuclear reactor.

Armed with this background information it becomes clear that the hardening of metal and heat treatment are very complicated processes, which must be controlled by a specialist to ensure that your components obtain the characteristics you desire. 

Because it is often only possible to see what we have done to your components under a microscope, heat treatment is also a question of trust.

We would be happy to advise you, personally and competently.  Your components are in safe hands with us.

Our comprehensive range of services are presented In the following pages.



Case hardening

Flame hardening


Hardening & tempering

Induction hardening

Low pressure carburizing


Solution Nitriding

Hardening tempering

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