Netizen Mr. Zhang asked, what kind of tool steel is better for punching 0.3mm thick SK5, with a material hardness of HV180-190. Currently, ASP23 is being used to punch more than 100000 times.
That shouldn’t be the case. ASP23 is a powder high-speed steel with a hardness of 64-66HRC and good wear resistance. It is made by punching 0.3mm thick SK5 hard material with a hardness of 180-190HV. It only needs to be punched 100000 times to produce a sharp edge, which is unacceptable. The smelting quality of ASP23 is questionable.
We have had similar cases for a long time. Mr. Chen from Zhongshan stamped 0.35 thick SK4 hard material with a hardness of 560HV. The punch originally used SKH51 high-speed steel was prone to wear and tear, and the product was prone to burrs.
But the punch was changed to Wu Dejian PM23 powder high-speed steel, which has been stamped more than 200000 times without cracking or wear.
Compared to your 100000, these 200000 times are two times worse. It’s still the harder material for stamping 560HV. The material is harder and the punch should be more prone to wear, but the punch life is twice as long as yours.
The factors that determine the wear resistance of tool steel are the type, morphology, particle size, and distribution of carbides. And for this working condition, everyone is using PM23 powder high-speed steel series products. The types and forms of carbides are the same, but the only difference is the particle size of carbides, whether they are distributed in a dispersed manner, which affects the wear resistance. The particle size and distribution are determined by the smelting quality.
And the material of the punched material in these two cases is the same, the tool steel used is the same, the thickness is thicker, the hardness is harder, but the service life is twice as long. Therefore, there is reason to suspect that the smelting quality of ASP23 by this netizen is questionable.
For those who like cheap prices, please note that the quality of smelting also determines performance. It is not foolish to think that the same material has the same performance, and the cheaper the better.
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Wu Dejian tool Steel is the user’s chief of staff and everyone who has used it buys it.