What are the factors affecting the hardness of NM400 wear-resistant steel?

The main factors affecting the hardness of NM400 wear-resistant steel are as follows:

1、 Chemical composition

Carbon content:

Carbon is one of the important elements that affect the hardness of steel. As the carbon content increases, the hardness of NM400 wear-resistant steel will correspondingly increase. This is because carbon can form hard carbides, such as iron carbide, which can enhance the hardness and wear resistance of steel.

However, excessive carbon content can also increase the brittleness of steel, reduce toughness and weldability. Therefore, in the production process of NM400 wear-resistant steel, it is necessary to control the carbon content reasonably to achieve a balance between hardness and toughness.

2、 Heat treatment process

Quenching temperature and time:

Quenching is one of the important heat treatment processes for improving the hardness of steel. During the quenching process, NM400 wear-resistant steel is heated to a certain temperature to transform its structure into austenite, and then rapidly cooled to transform austenite into martensite, thereby increasing the hardness of the steel.

Tempering temperature and time:

Tempering is one of the important heat treatment processes to eliminate quenching stress and improve the toughness of steel. During the tempering process, the quenched NM400 wear-resistant steel is heated to a certain temperature, held for a certain period of time, and then cooled. The tempering temperature and time also have a significant impact on the hardness of steel.

3、 Processing technology

Rolling process:

The rolling process also has a certain impact on the hardness of NM400 wear-resistant steel. During the rolling process, by controlling parameters such as rolling temperature and reduction rate, the microstructure and properties of the steel can be altered, thereby affecting its hardness.

Welding process:

The welding process also has a certain impact on the hardness of NM400 wear-resistant steel. During the welding process, the effect of welding thermal cycling can cause changes in the structure and properties of the steel, thereby affecting its hardness.

4、 Usage environment

Temperature:

Temperature also has a certain impact on the hardness of NM400 wear-resistant steel. Generally speaking, as the temperature increases, the hardness of steel will gradually decrease. This is because at high temperatures, the structure of steel undergoes changes, and the diffusion rate of atoms accelerates, resulting in a decrease in the strength and hardness of the steel.

Corrosive medium:

In corrosive media, the hardness of NM400 wear-resistant steel is also affected. Corrosive media will undergo chemical reactions with steel, causing corrosion on the surface of the steel, thereby reducing its hardness and wear resistance.

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