Metallic component with a ceramic coating

Abstract

This invention involves an alumina-based coating deposited on a steel or copper metallic component for enhanced anti-corrosion and electric insulation properties. The coated metallic component can be a bearing, laminate, shaft, gear, bolt, washer, bush or shim made of steels; or wire and hairpin winding made of copper.

What is claimed is: 
     
         1 . A method of depositing an alumina coating on a metallic component, the method comprising:
 applying a liquid electrolyte onto a metallic component;   applying a high electric voltage of 200-600 volts onto the metallic component;   depositing an aluminium hydroxide substance onto a surface of the metallic component; and   transforming the aluminium hydroxide substance to an alumina coating on the surface of the metallic component through high voltage electrical discharging in the liquid electrolyte.   
     
     
         2 . The method as claimed in  claim 1 , wherein the metallic component is a steel bearing. 
     
     
         3 . The method as claimed in  claim 1 , wherein the metallic component is a steel laminate. 
     
     
         4 . The method as claimed in  claim 1 , wherein the metallic component is a copper hairpin.