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After more than 10 years of research and development in the field of hardware stamping processing, Shenzhen Licao Precision Mold Co., Ltd. mainly provides stainless steel contact spring, precision hardware contact processing, hardware terminal processing, and so on. We have now established long-term cooperation with multiple Fortune 500 companies.

When brown rust spots appear on the surface of stainless steel when it comes into contact with the shrapnel, many people are surprised to think that stainless steel is not rusty, and the rusty ones are not stainless steel. It may be due to a problem with the steel quality. In fact, stainless steel can also rust under certain conditions.

Stainless steel materials have the ability to resist atmospheric oxidation, known as rust resistance. It also has the ability to corrode in media containing acids, alkalis, and salts - that is, corrosion resistance. However, the level of corrosion resistance varies depending on the chemical composition of the steel itself, the processing status of the contact fragments, usage conditions, and the type of environmental medium. For example, 304 has excellent rust resistance in a dry and clean atmosphere. If it is moved to coastal areas, it will quickly rust in sea fog containing a large amount of salt; And 316 performed well. So not any type of stainless steel can withstand corrosion and rust in any environment.

Stainless steel metal contact shrapnel is a stable chromium rich oxide film (protective film) formed on the surface of the material, which is extremely thin, sturdy, and fine, preventing the continued infiltration and oxidation of oxygen atoms, and achieving rust resistance performance. Once this protective film is constantly invaded by a certain substance, oxygen atoms in the air or liquid will continuously penetrate or iron atoms in the metal will continuously separate, forming loose iron oxide, and the metal surface will also be constantly corroded. This kind of surface facial mask is damaged in many forms, such as dust, metal particles, adhesive organic liquid, etc.