When stamping Q195 steel (3.0) and testing wear-resistant steel 6077, we switched to a medium-speed wire-cut EDM punch. The stamping press output was: 77,000 strokes for flat steel and 82,000 strokes for oval tubing. Since switching to the medium-speed wire-cut EDM punch, die life has jumped from 2,000 strokes to 80,000 strokes—a significant increase by several times. It seems that optimizing the die is also very important.
Mr. Hu was stamping 3.0-mm-thick Q195 steel. His original dies, made from locally purchased DC53 and Cr12MoV, would develop burrs after producing only a small number of parts. After he contacted me, I determined that since he was stamping 3.0-mm-thick Q195—a material that isn’t particularly hard but is somewhat thick—the burrs were most likely caused by material sticking to the die.
In fact, a hardness of 60 HRC is sufficient for stamping steel in terms of wear resistance. Guided by the principle of finding a low-cost solution and drawing on my experience with Mr. Huang’s case, I recommended that he use wear-resistant steel 6077.
Wear-resistant steel 6077 has a hardness of 60–63 HRC and offers three times the crack resistance of chromium steel; its performance far surpasses that of cold-work tool steels such as Cr12MoV, SKD11, and D2.
Mr. Huang was stamping square products from 3.0-thick pickled sheet metal. After switching to wear-resistant steel 6077, he told me that the blanking dies made from this material remained burr-free even after 150,000 stamping cycles—the cost-effectiveness and advantages of this material are very clear.
Since Mr. Huang was also stamping 3.0-thick material—just like Mr. Hu—and the pickled sheet was similar to Q195, with comparable material thickness, grade, and die operating conditions, I recommended that he use Wear-Resistant Steel 6077.
However, the first time he used Wear-Resistant Steel 6077, after stamping 2,000 products, burrs reappeared. Mr. Hu was very disappointed; he believed that the hardness of wear-resistant steel 6077 was insufficient.
I asked him to send the die back so I could test the hardness for him. Since we test the hardness of every piece of material we ship—we never ship low-hardness material—our wear-resistant steel 6077 is produced in a dedicated furnace using our proprietary heat treatment process combined with cryogenic treatment, ensuring a hardness of 60–63 HRC. Logically speaking, stamping iron shouldn’t develop burrs after just 2,000 cycles.
After receiving the die, I tested the hardness and confirmed it was 60–63 HRC. I sent him a video to show him the results. I noticed that the cutting edge of his die was very rough, with the wire-cutting marks still visible. I told him that while the hardness measurement was fine, I thought the surface finish of the cutting edge needed improvement because it was too rough. When stamping Q195 steel, poor mold surface finish would cause wear and result in burrs.
He found my explanation reasonable, so he had a new die cut using medium-speed wire EDM. To his surprise, the new die’s service life reached 80,000 stamping cycles—a significant improvement over the original 2,000 cycles.
I’d like to take this opportunity to remind everyone that if a die isn’t performing well or has a short service life, you can’t blame it entirely on the die steel. Sometimes, simply optimizing the die’s structure or even changing the machining method can multiply its service life, and the results are immediate. Anyone who understands dies knows that die design is ten thousand times more important than the die steel itself.
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Wu Dejian’s tool steel, the chief of staff of the user, bought everything he had used.