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1. The thickness is generally 20 μm Above m, the hardness is generally 800-900HV.

2. Hard chrome plating; Hard chrome plating process. It is to deposit a thick layer of chrome coating on various substrate surfaces, utilizing the characteristics of chrome to improve the hardness, wear resistance, mild and corrosion resistance of parts.

3. Hard chrome plating is a traditional surface plating technique that has been applied for over 70 years. The chrome plating layer has high hardness, wear resistance, corrosion resistance, and can maintain surface brightness for a long time. The process is relatively simple and the cost is relatively low. For a long time, chrome plating has been widely used as a wear-resistant and corrosion-resistant coating for mechanical components in addition to decorative coatings. plating hard chrome coating technology is often used to repair damaged parts.

4. The plating process of hard chrome can cause serious environmental problems. The chromic acid solution used in the chrome plating process can produce chrome containing acid mist and wastewater, and there are also some other drawbacks, such as: the hardness is generally 800-900HV, which is lower than some ceramic and cermet materials, and the hardness will also decrease with increasing temperature; There are microcracks in the chrome plating layer, which inevitably lead to penetrating cracks, causing corrosive media to penetrate from the surface to the interface and corrode the substrate, resulting in rust spots or even peeling off the surface of the coating; The deposition speed of plating process is slow, and plating 0.2-0.3mm thick coatings often takes 2-3 shifts, which is not conducive to the application of thick coatings. Therefore, the research field has been striving to find new processes to replace plating hard chrome. At present, many new processes have emerged and been applied and developed.