When the cold working die steel is working, the working part of the die bears great pressure, bending force, impact force and friction force due to the large deformation resistance of the processed material. Therefore, the normal scrapping reason of cold working die is generally wear and tear, and also premature failure due to fracture, collapse force and out of tolerance deformation.

冷作模具钢与刃具钢相比.有许多共同点。要求模具有高的硬度和耐磨性、高的抗弯强度和足够的韧性，以保证冲压过程的顺利进行、其不同之处在于模具形状及加I工艺复杂.而且摩擦面积大.磨损可能性大.所以修磨起来困难。

Compared with cutting tool steel, cold working die steel has a lot in common. The die is required to have high hardness and wear resistance, high bending strength and enough toughness to ensure the smooth progress of the stamping process. The difference is that the die shape and the process of adding I are complex, and the friction area is large and the possibility of wear is large, so it is difficult to repair.

因此要求具有更高的耐磨化模具工作时承受冲压力大.又由于形状复杂易于产生应力集中，所以要求具有较高的韧性;模具尺寸大、形状复杂.所以要求较高的淬透性、较小的变形及开裂倾向性。

Therefore, it is required to have higher wear resistance, and the die should bear large impact pressure when working. Because of the complex shape, it is easy to produce stress concentration, so it is required to have higher toughness; because of the large size and complex shape of the die, it is required to have higher hardenability, smaller deformation and cracking tendency.

总之，冷作模具钢在淬透性、耐磨性与韧性等方面的要求要较刃具钢高一些.而在红硬性方面却要求较低或基本上没要求(因为是冷态成形)，所以也相应形成了一些适于做冷作模具用的钢种.

In a word, the requirements of hardenability, wear resistance and toughness of cold working die steel are higher than those of cutting tool steel, but the requirements of red hardness are lower or basically not (because it is cold forming), so some kinds of steel suitable for cold working die are formed correspondingly