For stamping 2mm stainless steel, I still recommend 8566 anti-chipping steel because it offers excellent value for money.
This afternoon, I received inquiries from two customers stamping 2.0mm stainless steel. One had chosen the wrong material—Cr12MoV is prone to chipping—while the other used the very expensive ASP23 material, but it developed burrs at the wear points after only 10,000 stamping cycles, resulting in a very short service life. This led me to the conclusion that for punching 2mm stainless steel, I strongly recommend 8566 anti-chipping steel. Not only does it prevent chipping, but it also has a long service life. Compared to other mold steels, 8566 offers excellent value for money.
The first customer was punching 3.0mm holes in 2mm 304 and 430 stainless steel. They are currently using ASP23 powdered high-speed steel, but the dies chip after only 10,000 punches. Logically speaking, ASP23 is a powdered high-speed steel with a hardness of HRC 64–66 and excellent wear resistance. It is of high metallurgical quality and costs several hundred yuan per kilogram. When punching 3.0mm holes in 2mm stainless steel, it should not chip after just 10,000 pieces.
I recall a client of ours, Mr. Wang, who was punching 8mm holes in 5mm 304 stainless steel. He was punching a mesh pattern, with 6,000 holes per sheet. Previously, he had tried using ASP60, ASP23, 3V, and DC53 punches, but they all broke easily. He was constantly replacing punches—either one would break, or he’d have to switch to another—and he was spending all day changing punches, making it impossible to keep up with production. However, after switching to Yuhui 8566 anti-chipping steel, he was able to punch 36,000 holes without a single punch breaking.
Compared to this client, the material being punched is thinner and more expensive, yet its service life is still inferior to that of 8566 anti-chipping steel. Keep in mind that ASP23 costs three times as much as 8566. When you look at it this way, Yuhui 8566 offers excellent value for money.
The second client is working with 2.0mm-thick 304 stainless steel. The product has two sharp corners, and the punch always breaks at those points. Currently, they are using Cr12MoV—this is an incorrect choice of die steel. Chipping is to be expected; it would be unusual if it didn’t chip.
Cr12MoV is a high-carbon steel with 1.5% carbon content and a hardness of 58–62 HRC, offering good wear resistance. Its drawback is that it is hard and brittle, making it prone to chipping. When used for stamping 2mm-thick, hard stainless steel plates under harsh conditions involving sharp corners, Cr12MoV is bound to chip. You must use 8566 anti-chipping steel.
The chipping resistance of 8566 is four times that of high-speed steel SKH-9 and twice that of D2, with a hardness of 58–60 HRC. It is primarily designed to address chipping issues that high-hardness die steels like D2, DC53, and SKH-9 cannot resolve. This is particularly true for stainless steel stamping, sharp-corner stamping, narrow-flange stamping, and even narrow-flange conditions with a stamping ratio less than 1:1—cases where standard die steels fail to prevent chipping are all resolved with 8566.
Our client, Mr. Xia, performs single-step fine blanking of 2mm-thick 304 stainless steel. He told me that 8566 performs well for fine blanking 304 stainless steel, and producing 40,000 parts poses no problem.
After speaking with these two customers this afternoon, I believe that when stamping 2-gauge stainless steel, everyone should prioritize 8566 anti-chipping steel. Compared to other die steels, 8566 offers superior value for money—something other die steels simply cannot match. Using 8566 die steel for punch chipping is like night and day.
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Wu Dejian’s tool steel, the chief of staff of the user, bought everything he had used.