DRY SLIDING WEAR BEHAVIOUR OF PLASMA SPRAYED Al2O3-30%Mo, Mo & WC-12%Co COATINGS

The use of hard coatings to improve wear resistance of mechanical components is now well established. Of the advanced deposition techniques, plasma spraying is one of the most efficacious and adaptable process. Over the years, a variety of plasma sprayed ceramics, carbides and cermets have been tried as a replacement for the conventional coatings. The Molybdenum(Mo)is now being considered to be a future coating material for automotive engines. The WC–12%Co is well known for its high strength, hardness, toughness and wear resistance up to 5000C. The WC–Co coatings are widely used for tools, dies and wear resistant parts in variety of applications including machining, mining,metal cutting/forming, construction and other applications in the form of bulk parts or coatings. The fracture toughness of ceramics like Al2O3 can be enhanced by the addition Mo as a second phase. Due to its hardness and improved toughness Al2O3-Mo generally used in wear resistant components, such as water pump seals