It refers to the alloy tool steel used in making molds for thermoplastic processing of metal, such as die-casting die, hot extrusion die, hot forging die, hot heading die, etc. As the hot die works under high temperature and high pressure for a long time, the die material is required to have high strength, hardness, thermal stability and thermal fatigue resistance.
The hot die bears a great impact force in its work, and the cavity needs to be heated and cooled repeatedly, so the operating environment is extremely harsh. The following properties should be noted when selecting materials
(1) Good high-temperature strength and toughness; If the hot forging die works, it can bear very big impact force and high impact frequency.
(2) High hardness, good wear resistance and adhesion resistance; Friction wear, high temperature oxidation corrosion and iron oxide scrap grinding will occur due to billet deformation during work.
(3) Good thermal stability; When a hot die works, it comes into contact with hot metal billets
(4) Excellent resistance to heat and fatigue; In the work of repeated exposure to heat and cold
(5) Good thermal conductivity; So that the die will not accumulate too much heat, resulting in mechanical properties decline.