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1、 Improve the corrosion resistance of ferrous metals; At present, carbon steel is widely used in stamping parts, such as transmission lock, steel lining, etc. For carbon steel, how to improve its corrosion resistance is the key to its service life. Because of frequent contact with rain and sunlight, the first reason is that HCL may be released from the surface of PVC profiles under the effect of light and heat during aging, which has a strong corrosion effect on the zinc coating, which can explain why the corrosion occurs on the contact surface with PVC profiles;

2、 The coating is too thin. According to the relevant British standards, the thickness of zinc coating shall not be less than 40 in addition to the neutral salt spray test for 96 hours under severe conditions μ m。 The current domestic standards often only consider the time of salt spray test, without considering the coating thickness. If the passivation film is complete and good, 10 μ The coating of about m can pass the neutral salt spray test for 96 hours. Once the passivation film element is damaged, it is easy to rust. It is generally believed in the domestic electroplating industry that the 96 hour salt spray test is only to test the protective performance of the galvanized passive film. In addition, according to the use environment, the thickness of the galvanized layer is divided into three grades: good environment, general environment, and bad environment. The thickness of the galvanized layer is 61 μ m、121 μ M and 24 μ m。

The dies used for stamping are called stamping dies, or simply stamping dies. Stamping die is a special tool for batch processing materials (metal or non-metal) into required stamping parts. Stamping die is very important in stamping. Without qualified stamping die, batch stamping production will be difficult; Without advanced stamping die, advanced stamping process cannot be realized. Stamping process and die, stamping equipment and stamping materials constitute the three elements of stamping processing, and only when they are combined can stamping parts be obtained.
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