A netizen in the 227th live broadcast room said that DC53 needs deep cooling treatment to achieve superior performance. I think this is the cognition after being poisoned.
The performance of die steel is determined by a combination of alloy composition, internal structure, smelting quality, microstructure, heat treatment process, and these five factors, rather than a single factor. Cryogenic treatment is just one of the tempering processes, its main function is to reduce the content of residual austenite, improve hardness and wear resistance, which is helpful for improving the performance of die steel, but it does not play a crucial and decisive role.
The residual austenite content of high carbon cold work die steel after quenching is about 15-20%. Austenite is a soft and tough structure with low hardness, and these residual austenite are extremely unstable structures. During the use of the mold, over time, this residual austenite will still transform into martensitic structure. During the transformation process, the volume will expand, which will generate internal stress. When combined with tissue stress, excessive internal stress may cause changes in mold size, template deformation, cracking, or corner collapse. It will also reduce the wear resistance of the mold. Therefore, the residual austenite in die steel should not be too much.
The purpose of deep cooling is to lower the cooling temperature to below 0 ℃, reaching below minus 100 ℃ of the DC53 martensitic transformation termination line, in order to generate sufficient undercooling and provide power for the transformation of residual austenite. Compared with those that have not undergone deep cooling treatment, the hardness will increase by 1-2 degrees, and the wear resistance will also increase accordingly; Also, because its internal stress is reduced, the risk of mold deformation, dimensional changes, or cracking is reduced, thus achieving the goal of stabilizing the structure; This is the true purpose of deep freezing. But it doesn’t mean that as long as deep freezing is done, the performance of die steel will be superior. Don’t exaggerate it.
By heat treatment, the steel is given a hard martensitic structure, thereby improving the hardness, strength, and wear resistance of the mold. Heat treatment is an important way to strengthen molds, while cryogenic treatment is aimed at obtaining a harder martensitic structure. It is helpful in improving the performance of DC53, but it does not have the effect of reviving the dead.
To ensure the performance of die steel, we still need to comprehensively improve the smelting quality, purity, reduction of five harmful impurities, full forging, three forging and three pulling to obtain high-quality internal structure, as well as reasonable heat treatment process to obtain the desired organization. Only by doing so can we guarantee the performance and service life of die steel. However, it cannot be simply assumed that cryogenic treatment can change the properties of die steel, which is a misconception.
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I am Wu Dejian, the king of die steel, from Dongguan Yuhui Tool Steel. Yuhui Tool Steel is used by 3 Fortune 500 companies, and Kyocera has been purchasing Yuhui Tool Steel for 7 consecutive years. I have solved the difficult problems of mold material selection, production, and use for more than 4,000 enterprises. If you are hesitant when choosing die steel, or if the die steel you are currently using has a short service life, and you don’t know which material to use, welcome to come to me. I believe that in this regard, I can be your chief of staff and help you save money. Wu Dejian Tool Steel, the chief of staff of users, is well-received by those who have used it!
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