Question from a live stream viewer: What die steel is best for hot forging 316 stainless steel? My budget is around 50 yuan per kilogram—any recommendations? I’m currently using 2367 mold steel, but I can’t produce large quantities.
If we consider this question as a whole, there aren’t really any good recommendations. For mold steel priced around 50 yuan per kilogram, the 2367 you’re currently using is actually the most suitable option for you.
If we break the question down—what die steel is best for hot forging 316 stainless steel?—then I can answer that. For hot forging 316 stainless steel, the material is typically heated to 1100°C. The hot forging punch is prone to being fully heated through, and given the high total alloy content of stainless steel, the process demands excellent thermal wear resistance.
Thermal wear resistance is a comprehensive property that requires both high heat resistance and high hardness. Only die steel with high heat resistance—whose hardness is not annealed away during operation—can ensure red hardness. Furthermore, when combined with high hardness, its thermal wear resistance is optimized. Good thermal wear resistance ensures a high surface finish on the finished product; the punch is less likely to develop rounded corners, and issues such as die collapse or cracking are minimized, resulting in a longer service life for the punch.
For hot forging 316 stainless steel, the die steel must possess high heat resistance, high hardness, and high toughness. Overall, I recommend 8566 die steel, which offers high hardness, high heat resistance, and high toughness.
The heat resistance of 8566 is on par with that of high-speed steel SKH51; it has a hardness of 58–60 HRC and four times the toughness of SKH51. 8566 strikes the perfect balance between high heat resistance, high hardness, and high toughness—a feat that other die steels cannot achieve. 2367 does not possess these properties.
2367 has a carbon content of 0.38% and a molybdenum content of 2.7%, but its hardness is limited to 50 HRC. Even if its heat resistance were sufficient, its resistance to thermal wear is poor. The fact that production volumes remain low further confirms that 2367 is unsuitable for the hot forging of stainless steel.
Mr. Zhang from Zhejiang gave 8566 a five-star rating for hot forging 304 stainless steel, noting that the finished product has excellent surface finish, looking as if it were made from a tube. The reason 8566 achieves such a high surface finish is precisely because of its excellent thermal wear resistance; combined with its good toughness, it is less prone to thermal fatigue cracking during use. Since the punch does not crack or wear away, the finished product naturally has a superior surface finish.
Regarding the 316 stainless steel for hot forging mentioned by this user, what die steel is recommended?
If you’re seeking high efficiency and want your dies to last longer—even if the die steel is slightly more expensive, the cost per product will actually be lower—and you want to minimize die repair time, then you should consider using 8566 die steel. It can help you achieve high efficiency, long service life, and low operating costs.
If your cost target is around 50 yuan, then stick with 2367 die steel. At this price point, it’s the best option available—you’ll have to settle for lower-quality material from small foundries, otherwise the cost won’t be feasible.
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Wu Dejian’s tool steel, the chief of staff of the user, bought everything he had used.