Heat treatment process of A588 weathering steel plate

A588 weathering steel plate is a kind of low alloy high strength structural steel with atmospheric corrosion resistance. It is an atmospheric corrosion-resistant steel material, which is made of ordinary carbon steel by add a small amount of copper, nickel and other corrosionresistant elements. It has a wide range of applications, such as welding, bolting, and riveting structures.

The heat treatment process of A588 weathering steel plate is mainly to improve its mechanical properties, that is to adjust the microstructure to obtain suitable mechanical properties, to meet the requirements of use, and to manufacture parts with specific properties and uses. Heat treatment generally includes annealing, quenching and tempering, etc. The following is the heat treatment process of A588 weathering steel plate.

1. Annealing

Annealing of A588 weathering steel plate is mainly used for stress relief. For the annealing process, the A588 weathering steel plate can be placed in the annealing furnace in the form of coiling (that is, coiling or vibrating) or short (loose) pieces, and heated to a temperature of 30-50°C above the critical temperature of steel, and then slowly cooled.

2. Normalizing

Normalizing is a heat treatment process used to refine the crystalline structure and improve the mechanical properties of A588 weathering steel plate. Normalizing can reduce the hardness and brittleness of steel, homogenize the microstructure, refine the grain size and improve the mechanical properties of steel.

3. Quenching

Quenching of A588 weathering steel plate is mainly used to increase the hardness of steel. After the steel is heated to the austenitizing temperature, it is cooled in the quenching medium. Before quenching, the heated steel parts must be preliminarily tempered to lower their temperature by at least 10-15°C and the tempering temperature must be within 200-300°C.

4. Temperature

Tempering of A588 weathering steel plate is a process of reheating the quenched steel parts to a lower temperature, so that the structure and mechanical properties of the steel can be improved. The tempering temperature is generally 50-200°C below the critical temperature so that the structure formed after quenching can get the best combination of strength and plasticity.

After the heat treatment of A588 weathering steel plate, its surface should be free from scale and its internal organization should be uniform and tight. The strength and toughness of the heat treated material are greatly improved, and its plasticity and machinability are also significantly improved. The surface of the heat-treated parts is clean and the mechanical properties are stable