Plastic die steel is a kind of die steel which is pressed by fine powder or granular plastic under heating condition. The plastic mould is heated and pressed continuously, and is corroded by friction and harmful gas to a certain extent. Therefore, the plastic mould steel is required to have enough strength and toughness at 200 ℃, and has high wear resistance and corrosion resistance.

随着塑料工业的迅速发展，塑料模具钢逐渐发展成为一个体系，它涉及了从结构钢到工具钢，从碳素钢到合金钢的许多钢种。

With the rapid development of plastic industry, plastic mold steel has gradually developed into a system, which involves many kinds of steel from structural steel to tool steel, from carbon steel to alloy steel.

根据模具钢的强化方式或服役特性，可将塑料模具钢大体分为渗碳型塑料模具钢、预硬型塑料模具钢、整体淬硬型塑料模具钢、时效硬化型塑料模具钢、耐蚀型塑料模具钢等。

According to the strengthening mode or service characteristics of die steel, plastic die steel can be roughly divided into carburizing plastic die steel, pre hardening plastic die steel, integral hardening plastic die steel, age hardening plastic die steel, corrosion-resistant plastic die steel, etc.

渗碳型塑料模具钢主要用于制造承受载荷较小、强度指标要求不高的塑料模具。它包括碳素渗碳钢与合金渗碳钢，钢中碳的质量分数一般在0.1%~0. 25%范围内，退火后硬度较低，具有良好的可加工性，也可以采用挤压成形法制造模具。

Carburized plastic mould steel is mainly used to manufacture plastic mould with small load and low strength index. It includes carbon carburizing steel and alloy carburizing steel. The mass fraction of carbon in the steel is generally in the range of 0.1% ~ 0.25%. The hardness of the annealed steel is low, and it has good machinability. The extrusion forming method can also be used to manufacture the die.

经渗碳、淬火与低温回火后，模具型腔表面获得高硬度和高耐磨性，而心部具有一定的强度和良好的韧性，同时也保证了较好的抛光性能。

After carburizing, quenching and low temperature tempering, the surface of the mold cavity has high hardness and high wear resistance, while the core has certain strength and good toughness, and good polishing performance is also ensured.