The first point: wear resistance
When the blank is plastically deformed in the mold cavity, it moves and slides along the appearance of the cavity, causing a sharp conflict between the appearance of the cavity and the blank, and then causing the mold to fail due to wear. Therefore, the abrasion resistance of the material is one of the most basic and important functions of the mold.
Hardness is the primary factor affecting wear resistance. In general, the higher the hardness of the mold parts, the smaller the amount of wear and the better the wear resistance. In addition, the abrasion resistance is also related to the type, quantity, shape, size, and dispersion of carbides in the guess.
Second point: strong patience
Most of the working conditions of the mold are very harsh, and some often bear a large impact load, and then cause brittle cracking. In order to prevent the mold parts from being brittle during operation, the mold must have high strength and resistance.
The resistance of the mold mainly depends on the carbon content, grain size and microstructure of the material.
The third point: fatigue cracking function
During the operation of the mold, under the long-term effect of cyclic stress, it often leads to fatigue cracking. The methods include small energy repeatedly impacting fatigue cracking, stretching fatigue cracking, touching fatigue cracking, and zigzag fatigue cracking.
The fatigue cracking function of the mold depends primarily on its strength, resistance, hardness, and the content of inclusions in the material.
Fourth point: high temperature function
When the working temperature of the mold is higher, the hardness and strength will be reduced, leading to the wear of the mold or plastic deformation and failure. The mold data should have high resistance to tempering to ensure that the mold has higher hardness and strength at the operating temperature.
Fifth point: cold and heat fatigue resistance
Some molds are repeatedly heated and cooled during the operation, which causes the surface of the cavity to be stretched and pressure to change the stress, causing the surface to crack and fall off, increasing the conflict force, preventing plastic deformation, reducing the accuracy of the scale, and then causing Mold failure. Cold and hot exhaustion is one of the most important ways of failure of hot work molds, and this type of mold should have a high resistance to cold and hot exhaustion.
Sixth point: corrosion resistance
During the operation of some molds, such as plastic molds, due to the presence of chlorine, fluorine and other elements in the plastic mold, they will decompose and release strong corrosive gases such as hci and hf upon heating, which will corrode the appearance of the mold cavity, increase its surface roughness, and increase wear and tear .