The main purpose of heat treatment of steel, is to change its properties. Thanks to the heat treatment of steel acquired properties such as ductility, toughness, strength, endurance, and others. Heat treatment were divided into: 1. annealing. Annealing of steel used in cases where it is necessary to obtain a uniform structure. The annealing process involves three successive stages, firstly, heating steel to a predetermined temperature, Secondly, exposure of steel at a given temperature, and thirdly, slow cooling in the furnace. There are two kinds of annealing.
Upon annealing a second kind of changes depending on the phase transitions are observed. When annealing the 2 nd kind of steel acquires the equilibrium structure. 2. quenching. Tempering – a heat treatment of steel, which results in the steel with the maximum non-equilibrium structure and with an abnormal level of properties. Quenching process proceeds in three consecutive stages: the first stage – is heating steel to a predetermined temperature, the second stage – an extract of steel at this temperature, the third stage – the rapid cooling of steel.
3. vacation. Breakfast – a type of heat treatment steel is to reduce internal tension steel. 4. normalization. Normalization – a method of heat treatment consisting in heating the steel to the required temperature, then the exposure began, and then cooling the steel in air. To carry out the correct heat treatment of steel and produce the desired results, but also to determine the correct heating temperature, cooling medium and the type of equipment is necessary to clearly define the type of machined steel. When you select a brand of metal that of the item, you should pay attention to the operational and technological properties of steel. Given the brand of steel tempering temperature is determined range from 530 to 1300 C. To determine the heating temperature using a special device called a pyrometer. A cooling medium can serve as a furnace, air cooled, and others may occur gradually or immediately. Thus, the heat treatment of steel (metal) means the processing of products with thermal effects for changes in the structure and properties of the product in the right direction.