Wire drawing in deep-drawing dies is an extremely common phenomenon—and even a major pain point in the deep-drawing industry. During my 296th live stream, several viewers reported issues with wire drawing in their deep-drawing dies. Three of these cases left a particularly strong impression on me; they all asked what type of die steel to use to prevent wire drawing.
The first was drawing 3-thick cold-rolled sheet to produce automotive control arm parts. They were currently using Cr12MoV with TD heat treatment, but stringing occurred after producing only a few parts. This was due to incorrect material selection.
The second viewer was drawing 0.7-thick DC04 material and asked which die steel to use to minimize stringing.
For these two viewers, I recommended using wear-resistant steel 6077. I have a client who deep-draws 0.7-thick galvanized sheet metal for motor housings, with a draw depth of 30 mm. When using DC53, the die would develop wire marks after producing only a small number of parts, leading to frequent customer complaints.
After he contacted me, I recommended he use wear-resistant steel 6077. He reported that a die made from 6077 produced 3 million parts before needing replacement—I was very satisfied with that result. Wear-resistant steel 6077 will also develop wire marks after a certain number of products, but it doesn’t happen very often. I just polish it, and it’s ready to use again—no complaints from the customer. Wear-resistant steel 6077 isn’t expensive, but it performs much better than DC53; a single die produced 3 million products without being scrapped. As a die manufacturer, I’m happy as long as the customer doesn’t complain.
The first two users mentioned here are drawing steel, and even with Cr12MoV plus TD treatment, they still experience stringing. I think wear-resistant steel 6077 is definitely worth a try. If you’re willing to add a coating, the results will be even better.
The third user is drawing 0.6-thick 304 stainless steel. He’s already using M35 high-speed steel with a hardness of 65 HRC, but it still tends to string.
This is likely because the M35 you purchased was of poor smelting quality, with too many microcracks in its microstructure, leading to mold sticking and stringing. There are two solutions: either apply a coating to the M35 or switch to PM23 powdered high-speed steel.
Based on these users’ questions, I believe that stringing in drawing dies may be a common industry pain point—a widespread phenomenon.
I think that when selecting steel for drawing dies, smelting quality should be a top priority. Steel free of segregation and microcracks in its microstructure is the fundamental and effective way to prevent stringing in drawing dies.
For drawing dies used with iron materials, you should use at least wear-resistant steel 6077 or non-stick 8503 die steel. These can be used for direct drawing without the need for surface coating. Once they’ve reached a certain production volume and show wear, simply polish them, and they can be reused—this is a low-cost material option. If you’re willing to add a coating, it will yield twice the result with half the effort.
Second, if your budget allows and the die is not too large or material-intensive, you can use powdered high-speed steel or tungsten carbide—these work very well.
It’s important to note that Cr12MoV should be used with caution in drawing dies—or better yet, avoided entirely—as dealing with wire drawing defects caused by it is very troublesome.
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Wu Dejian’s tool steel, the chief of staff of the user, bought everything he had used.