The regularity and process enhancement for Cr (Ⅲ) electrodeposition

Chrome plating is widely used due to excellent mechanical and anti-corrosion performance. However, the traditional hexavalent chromium plating process is highly toxic and polluting. The trivalent chromium plating process with low toxicity has received widespread attention. However, it is difficult to obtain thick chromium coating by trivalent chromium plating technology. Continuous plating and stable plating solution are the key issue. In this paper, the effects of pulse plating and bath flow on chromium electrodeposition were investigated. Both pulse current plating and bath flow can promote the transfer of by-products generated during the electroplating process. However, pulse plating will reduce the efficiency of chromium electrodeposition, and bath flow can enlarge the electrodeposition efficiency of chromium and promotes the formation of thick chromium. By bath flow with the rate of 50 mL/min, thick chromium coating with compact surface structure is obtained and the thickness is up to 41 μm after 60 min plating. Deposition rate is up to 0.68 μm/min.