Working conditions of die material selection compiled by Qingdao metal design company

1. Wear resistance

When the blank is plastically denatured in the mold cavity, it flows and slides along the cavity surface, resulting in severe friction between the cavity surface and the blank, resulting in the failure of the mold due to wear. Therefore, the wear resistance of materials is one of the basic and important properties of molds. In general, the higher the hardness of die parts, the smaller the wear, and the better the wear resistance. In addition, the wear resistance is also related to the type, quantity, shape, size and distribution of carbides in the material.

2. Strength and toughness

Most of the working conditions of dies are very bad, and some often bear large impact load, resulting in brittle fracture. In order to prevent sudden brittle fracture of die parts during operation, the die should have high strength and toughness. The toughness of the die mainly depends on the carbon content, grain size and microstructure of the material.

3. Fatigue fracture performance

During the working process of die, fatigue fracture is often caused by the action of cyclic stress. The fatigue fracture performance of the die mainly depends on its strength, toughness, hardness and the content of inclusions in the material.

4. High temperature performance

When the working temperature of the die is high, the hardness and strength will decrease, resulting in early wear or plastic deformation and failure of the die. Therefore, the die material should have high tempering stability to ensure that the die has high hardness and strength at working temperature.

5. Cold and hot fatigue resistance

Some molds are in the state of repeated heating and cooling in the working process, so that the surface of the cavity is under the action of tensile and pressure strain stress, resulting in surface cracking and peeling, aggravating friction, hindering plastic deformation and reducing dimensional accuracy, resulting in mold failure.

6. Corrosion resistance

When some molds, such as plastic molds, work, due to the presence of chlorine, fluorine and other elements in the plastic, they decompose and precipitate strong corrosive gases such as HCI and HF after heating, eroding the surface of the mold cavity, increasing its surface roughness and aggravating wear failure.