1. Wear resistance

When the billet undergoes plastic deformation in the mold cavity, it flows and slides along the surface of the cavity, causing severe friction between the cavity surface and the billet, leading to the failure of the mold due to wear. So the wear resistance of materials is one of the most basic and important properties of molds.

Hardness is the main factor affecting wear resistance. In general, the higher the hardness of mold parts, the smaller the wear amount, and the better their wear resistance. In addition, wear resistance is also related to the type, quantity, morphology, size, and distribution of carbides in the material.

2. Strong resilience

The working conditions of molds are mostly very harsh, some of which often bear large impact loads, leading to brittle fracture. To prevent sudden brittle fracture of mold parts during operation, molds should have high strength and toughness. The toughness of the mold mainly depends on the carbon content, grain size, and microstructure of the material.

3. Fatigue fracture performance

During the working process of the mold, long-term cyclic stress often leads to fatigue fracture. Its forms include small energy multiple impact fatigue fracture, tensile fatigue fracture, contact fatigue fracture, and bending fatigue fracture. The fatigue fracture performance of a mold 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 mold is high, it will cause a decrease in hardness and strength, leading to early wear or plastic deformation of the mold and failure. Therefore, the mold material should have high tempering stability to ensure that the mold has high hardness and strength at working temperature.

5. Cold and hot fatigue resistance

Some molds are in a state of repeated heating and cooling during the working process, causing the surface of the mold cavity to be subjected to tensile and compressive stress, causing surface cracking and peeling, increasing friction, hindering plastic deformation, reducing dimensional accuracy, and ultimately leading to mold failure. Cold and hot fatigue is one of the main forms of failure in hot working molds, and such molds should have high resistance to cold and hot fatigue.

6. Corrosion resistance

Some molds, such as plastic molds, when working, due to the presence of elements such as chlorine and fluorine in the plastic, they decompose and release strong corrosive gases such as HCI and HF after being heated, eroding the surface of the mold cavity, increasing its surface roughness, and exacerbating wear and failure.