Generally, it is divided into two categories according to MIM metal materials (iron-based and stainless steel materials), and stainless steel materials are widely used (316L / 17-4PH,)

316 material is the star material of choice for MIM appearance parts due to its unique properties. Stainless steel is a high-alloy steel that can resist corrosion in air or chemical corrosion media. Stainless steel has an elegant appearance and good corrosion resistance, without going through. It is a kind of steel that uses surface treatment processes such as color plating to exert the inherent appearance properties of stainless steel and is used in many aspects. It is usually called stainless steel. From the metallographic point of view, because the stainless steel contains chromium, a very thin chromium film is formed on the surface. This film is separated from the oxygen intruding into the steel and plays a role in corrosion resistance. In order to maintain the inherent corrosion resistance of stainless steel, steel must contain more than 12% chromium.

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