Plastic mold steel is the raw material for the preparation of plastic mold. The performance of plastic mold steel is closely related to plastic production enterprises. Therefore, only by understanding its types can we help us better choose the suitable mold. So, what kinds of plastic mold steel?

1、渗碳型

1. Carburizing type

渗碳钢退火后硬度低、塑性好，可以采用冷挤压成型。渗碳型塑料模具钢含碳量较低，常加元素Cr，同时加入适量的Ni、Mo、V，以提高淬透性和渗碳能力，退火后的应对≤100HBS。

The annealed carburized steel has low hardness and good plasticity, so it can be formed by cold extrusion. The carbon content of carburized plastic die steel is low. The element Cr is often added, and the appropriate amount of Ni, Mo and V are added to improve the hardenability and carburizing ability. The response after annealing is less than or equal to 100 HBS.

2、预硬型

2. Pre hardening type

预硬型是为避免大、中型精密模具热处理后的变形，保证模具的精度和使用性能而开发的一种模具钢。预行调质处理，硬度为30-40HRC。这类钢一般为中低碳合金钢，含碳量为0.35%-0.65%，常用合金元素有Cr、Ni、Mn、V等，为改善其切削性，加入S、Ca等。

Pre hardening die steel is a kind of die steel developed to avoid the deformation of large and medium precision dies after heat treatment and ensure the accuracy and performance of dies. The hardness is 30-40hrc. This kind of steel is generally medium and low carbon alloy steel with carbon content of 0.35% - 0.65%. The common alloy elements are Cr, Ni, Mn, V, etc. in order to improve its machinability, s, CA, etc. are added.

3、调质型是模具在加工后，再进行调质处理，使模具的性能更佳。主要有3类

3. Quenched and tempered mold is processed, and then quenched and tempered, so that the performance of the mold is better. There are three main categories

1）45、55等碳素钢，适宜于形状简单或精度要求不高、使用寿命不长的模具。

1) 45, 55 and other carbon steel, suitable for simple shape or accuracy requirements are not high, service life is not long mold.

2）40CrMo、42CrMo。前者有良好的低温冲击韧性和低的缺口敏感性，适宜制作中型模具；后者属于高强度钢，且有较高的疲劳极限，低温冲击性好，适宜制造要求一定强度和韧性的大、中型塑料模具。

2）40CrMo、42CrMo。 The former has good low temperature impact toughness and low notch sensitivity, so it is suitable for manufacturing medium-sized moulds; the latter belongs to high strength steel with high fatigue limit and good low temperature impact property, so it is suitable for manufacturing large and medium-sized plastic moulds requiring certain strength and toughness.

3）38CrMoAl、5CrNiMo。前者适用于PVC、PC的塑料模具。后者主要用于使用温度较高、耐磨性要求高的模具，如热固性塑料模。

3）38CrMoAl、5CrNiMo。 The former is suitable for PVC, PC plastic mold. The latter is mainly used for high temperature, high wear resistance mold, such as thermosetting plastic mold.

4、时效硬化型

4. Age hardening type

时效硬化型主要用于制造高精度、复杂型腔塑料模具，昂贵。有马氏体时效硬化和析出沉淀硬化钢两大类。

The age hardening type is mainly used for manufacturing high precision and complex cavity plastic mold, which is expensive. There are two kinds of steels: Maraging hardening and precipitation hardening.

5、耐蚀型

5. Corrosion resistant

主要用于有聚氯乙烯、聚苯乙烯、ABS加抗燃树脂等生产中会分解出腐蚀性气体这一类的材料。

It is mainly used in PVC, polystyrene, ABS and fire-resistant resin, which can decompose corrosive gas.