In order to make steel harder, a common treatment is to Quench and Temper, a process that involves heating, rapid cooling, and re-heating the steel. However, while Quench and Temper is common, it is ENDURA’s unique take on this process that gives it its TRIP EFFECT properties.
The Quenching Process
The first step in the process is to heat the steel to over 870℃. Heating to this temperature causes a grain structure called “austenite” to form. An austenitic grain structure produces a very soft metal.
After the steel has been heated, it needs to be rapidly cooled, or “Quenched”. As the steel is quenched, the austenitic grain structure is transformed in different grain structures such as martensite, ferrite, or pearlite depending how quickly the cooling takes place.
There are different methods for cooling:
- Water: cheapest and fastest but can cause cracking (may use salt water)
- Forced air: the slowest and must be rigorously controlled
- Oil: provides a slower cooling rate, reduces distortion and cracking, and is the most expensive
All methods of quenching require uniform controlled cooling in order to prevent warping or cracking.
The Tempering Process
After being quenched, the metal is very hard and very brittle. To reduce the brittleness, the steel is reheated for a set period of time to between 200℃ and 600℃. Depending on time and temperature during this process, the hardness is reduced but the ductility is increased. The steel is then cooled in air.
ENDURA’s Oil Quenched Advantage
ENDURA Steel is the only wear steel that is “Oil Quenched”. This is an expensive process but yields a homogeneous micro structure and the TRIP EFFECT (Transformation Induced by Plasticity). This means less cracking, gouging, and tearing of the steel compared to other wear steels, which in turn means longer wear life and reduced down time.