Although XPM series materials are classified into diffe […]
Although XPM series materials are classified into different grades, their hardness ranges are generally 359-400hb (38-42hrc), the main difference is that the smelting processes used are different, and the purity of steel is also very different.
The factory hardness is not fixed, but tempered according to the requirements of the first-hand orderer.
Properties of plastic mould steel
When using Cr12 Steel or high speed steel as cold working die, a very prominent problem is that the steel is brittle and easy to crack in use. Therefore, it is necessary to refine carbides by full forging. In addition, new steel grades should be developed.
The focus of developing new steel grades should be to reduce the carbon content of steel and the amount of carbide forming elements. The following new steel grades are developed and popularized in China, as shown in table 4.11.
Cr4W2MoV steel has the advantages of high hardness, high wear resistance and good hardenability, and has good tempering stability and comprehensive mechanical properties. The die for making silicon steel sheet with dry process can increase the service life of Cr12MoV steel by more than 1-3 times, but the forging temperature range of Cr4W2MoV steel is narrow, and the forging crack is found in Hexian.
The forging temperature and operation specification should be strictly controlled to confirm that cr2mn2siwmov steel has low quenching temperature, small quenching deformation and high hardenability. 7w7cr4mov steel, which is called as free quenching micro deformation die steel, can replace W18Cr4V and Cr12MoV steel. Its characteristics are that the carbide heterogeneity and toughness of steel are greatly improved.