Heat treatment is a method of changing the physical properties of a metal. We heat the metal above a certain critical temperature and hold it there for a certain amount of time, then let it cool at different rates to get the mechanical properties we want. Necessary. This is called heat treatment of steel.
Heat treatment is carried out during various molding operations. It removes internal stresses, refines plasticity and cutting properties and improves the overall mechanical properties of the metal.
There are four main operations of heat treatment as follows:
1. Standardizing. The steel is heated above the critical temperature (30-50°C) and held for a certain time and cooled at room temperature. This is a natural cooling method.
2. Annealing. We heat the steel above the critical temperature and allow it to cool very slowly. This makes it softer than before and easier to work with.
Normalizing has some advantages over annealing. Not only does normalizing cool faster than annealing, but normalizing also has a much shorter lead time than annealing. Therefore, when both normalizing and annealing meet our requirements, it is very economical for us to use normalizing instead of annealing.
3. Quenching. We heat the metal above the critical temperature, harden it by rapid cooling and then quench it in water or other liquid. This is the fastest of all methods of cooling the metal. The faster the temperature drops, the faster the metal cools. The metal becomes harder.
4. workout. Tempering is usually done after quenching. Tempering together with quenching is called tempering. Metals that cool slowly are less likely to develop internal stresses than metals that cool quickly. In other words, the plasticity and mechanical properties of the metal decrease during quenching. The purpose of tempering is to eliminate internal stresses and improve its overall properties.
