When cold working die steel is working, due to the large deformation resistance of the processed material, the working part of the die bears great pressure, bending force, impact force and friction force. Therefore, the normal scrapping reason of cold working die is generally wear, and it also fails in advance 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。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。

Cold working die steel has much in common with cutting tool steel. The die is required to have high hardness and wear resistance, high bending strength and sufficient toughness to ensure the smooth progress of the stamping process. The difference lies in the complex die shape and i-addition process, large friction area and high wear possibility, so it is difficult to repair. Therefore, it is required to have higher wear resistance. The die bears large impact pressure when working. Due to the complex shape and easy to produce stress concentration, it is required to have high toughness; The die has large size and complex shape, so it requires high hardenability, small 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，例如，发展了高耐磨、微变形冷作模具用钢及高韧性冷作模具用钢等。

In short, the requirements for hardenability, wear resistance and toughness of cold working die steel are higher than those of cutting tool steel, but the requirements for red hardness are lower or basically not (because it is cold forming), so some steels suitable for cold working die have been formed accordingly. For example, high wear resistance, micro deformation cold working die steel and high toughness cold working die steel have been developed.