Process Surface coating process where the workpiece through an anode-cathode reaction is coated with a thin decorative layer of hexavalent chrome with a black tone.
Process Surface coating processing the workpiece through an anode-cathode reaction in a salty solution is coated with a thin and ductile layers of zinc.
Process Polishing process where the workpiece is immersed in a heated electrolyte and where the workpiece is subjected to a current so that its surface is partially ionized and dissolved.