Last night, Mr. Ke, a long-time client I hadn’t been in touch with for years, called to ask about stamping 0.5mm-thick titanium sheets with some stretching involved. He currently uses ASP60 powdered high-speed steel, but after producing just a few thousand parts, burrs start to form, and the die becomes coated with a lot of metal shavings. Do you have any suggestions on how to solve this?
Titanium sheets are very soft and difficult to punch; they often exhibit a phenomenon where the material breaks but the thread remains connected, making it hard to cut cleanly. Therefore, the die steel must be selected to be both non-stick and highly wear-resistant. However, since you are already using ASP60 powdered high-speed steel and are still experiencing burrs after producing just a few thousand parts, this should not be happening.
Mold steel produced using advanced powder metallurgy processes does not suffer from segregation issues or micro-cracks, and therefore should not experience material adhesion or adhesive wear. Furthermore, ASP60 is a high-alloy, high-hardness, and high-wear-resistant high-speed steel with a carbon (C) content of 2.3%, cobalt (Co) content of 10.8%, and vanadium (V) content of 6.0%, achieving a quenched hardness of 67–69 HRC. As an expensive die steel costing nearly 1,000 yuan per kilogram, it should not develop issues after producing only a few thousand parts.
This indicates that the ASP60 powdered high-speed steel he is currently using was produced using an incorrect smelting process, resulting in microstructural segregation and the presence of fine cracks. Otherwise, it would not have developed adhesive wear caused by material sticking so quickly after punching just a few thousand products.
His experience demonstrates once again that a correct grade does not necessarily equate to correct performance.
This reminds me of Mr. Huang, who makes cutting blades. His blades are used to cut single strands of 0.15mm stainless steel wire. He used to use tungsten carbide blades, but they kept chipping. After switching to Yuhui PM60 powdered high-speed steel, they lasted for over half a year. Last time, I tried to save money and bought PM60 from another supplier, but sometimes they’d chip within just a few days—it was infuriating. Your products are still the most reliable.
Speaking of which, when stamping 0.5mm-thick titanium sheets with some stretching involved, PM23 powdered high-speed steel is usually sufficient. It doesn’t suffer from material adhesion, abrasive wear, or stringing issues. Our Mr. Xie has actually praised Yuhui’s PM23 powdered high-speed steel.
Mr. Xie manufactures forming dies for titanium tubes. When he used tungsten steel, the die would stick—especially on the side walls—causing surface scratches on the products. However, after switching to Yuhui PM23 powdered high-speed steel, the sticking problem was completely resolved. The customer is very pleased, and I’m happy too, so I wanted to let you know.
However, Mr. Ke is currently using ASP60 powdered high-speed steel, which has better wear resistance, to stamp 0.5mm titanium sheets. Yet, after just a few thousand cycles, burrs appear, and there is a significant amount of powder residue stuck to the die. This indicates that the quality of his ASP60 steel is too poor, with severe microstructural segregation and numerous microcracks. There are two solutions. One is to perform a TD treatment on his current ASP60 mold to improve surface finish and eliminate the powder adhesion issue, which will naturally prevent burrs from forming. The other solution is to switch to ASP60 with better smelting quality.
Mr. Ke’s experience once again demonstrates that selecting the correct grade of die steel does not guarantee optimal performance. The actual effectiveness of die steel is often determined by factors such as smelting quality, internal structure, microstructure, and heat treatment processes. If the smelting quality of the die steel is poor, even the most expensive grade will be a waste of money.
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Wu Dejian’s tool steel, the chief of staff of the user, bought everything he had used.