During the 296th live stream, a viewer asked: “When punching 0.2mm TA1 titanium sheet with SKD11 dies and punches, there is significant burr formation. SKD11 dies can only produce 20,000–30,000 parts before burrs appear. What type of die steel should be used for punching 0.2mm TA1 titanium sheet?”
Titanium has excellent strength and toughness, with a typical hardness of 40 HRC. Although it is only 0.2 mm thick, titanium sheet is very ductile, making it difficult to punch. It is prone to tearing without clean separation or getting stuck during the punching process. Choosing SKD11 for punching titanium is definitely a mistake. Fortunately, since SKD11 is such an inexpensive material and can still produce 20,000–30,000 parts, you should consider yourself lucky.
A while back, a netizen asked about punching 0.5 mm pure titanium using an SKH-9 high-speed steel punch. After 5,000–6,000 cycles, burrs would appear, and they couldn’t resolve the issue, so they asked me what die steel to use.
Die failure patterns when punching titanium sheets are very consistent: burrs appear after only a few products have been punched. This type of adhesive wear caused by material adhesion is generally due to the wrong choice of die steel. For stamping very soft titanium sheets, PM23 powdered high-speed steel is the standard material.
PM23 has a hardness of 64–66 HRC; its high hardness ensures excellent wear resistance. Crucially, the powder metallurgy process eliminates segregation issues, preventing material adhesion to the die.
Mr. He was stamping 1.2mm-thick titanium sheet with parts featuring sharp corners and narrow edges, which often caused material to fly off. He had previously used ASP23, but it only lasted for 60,000 stampings before burrs appeared. Switching to ASP60 made things even worse—the narrow edges were prone to chipping, it was exorbitantly expensive, and its service life was even shorter, making it a very poor investment. After he contacted me, I recommended that he use Yuhui PM23 powdered high-speed steel.
He told me that PM23 delivers excellent punching results; his punches no longer chip, and the service life is consistently around 100,000 cycles—which is far better than ASP60. ASP60 not only chips easily but also has a very short service life and is ridiculously expensive.
A viewer in the livestream asked about punching 0.2-thick TA1 titanium sheet; when using SKD11, significant burrs appeared after just 20,000–30,000 cycles. You’ve chosen the wrong material. If you don’t want to mess around with other options, just go straight with PM23.
Here’s a reminder for everyone: whenever you’re punching titanium, no matter the thickness, PM23 is your go-to starting material. Not only do you need PM23 powdered high-speed steel, but you also need material with high smelting quality—free of segregation and microcracks—to prevent sticking to the die and stringing. If you buy powdered high-speed steel with poor smelting quality, it will still cause stringing.
A while back, two users asked me about this. They couldn’t figure out why their 0.2 and 0.3 titanium sheets—even though they were using ASP60—started developing burrs after only about 10,000 stamped parts.
The reason is that the ASP60 you purchased was of very poor smelting quality—it contained segregation issues and microcracks, which caused material adhesion and adhesive wear during the punching process, resulting in burrs. This type of adhesive wear has nothing to do with hardness levels; it’s entirely related to the quality of the smelting process.
For stamping titanium, a die hardness of 64–66 HRC is already highly wear-resistant. PM23 also offers good resistance to chipping, so it’s a safer choice for dies with narrow edges.
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Wu Dejian’s tool steel, the chief of staff of the user, bought everything he had used.