2.7 Surface finishing

• Paint


  A coloured substance which is spread over a surface and dries to leave a thin coating
• Dip coating


  A finishing process used to apply a polymer coating to metal
• Electroplating


  The part to be coated is placed in a chemical bath and a current is passed through it to build up a coating
• Electrolysis


  An electroplating process where an anode gradually dissolves and builds up as a coating on the cathode
• Anodising


  An electroplating process where a protective oxide layer is formed on the metal part being plated
• Galvanising


  Applying a coating to steel by dipping it in molten zinc
• Polishing


  The process of smoothing the surface of a part by removing or wearing away a small amount of material
• Painting


  • Relatively quick and low-cost way to increase the corrosion resistance and improve the appearance of a bare metal part
• Dip coating


  • The metal part is heated and placed in a fluidised bed of the polymer
• Electroplating


  • Involves placing a metal part in a chemical bath and using electricity to build up a coating
• Galvanising


  • Applies a coating to steel by dipping it in molten zinc
• Polishing


  • Involves removing a tiny amount of material of the surface of the part making it smoother and shinier