US Patent 7718221 Coatings for metal casting parts

The method is disclosed for coating or impregnating a metal tool with a metal oxide to render the metal part more resistant to liquid metal attack or micro-welds. The method includes the steps of applying a liquid metal carboxylate composition, or a solution thereof, to a substrate material, and exposing the substrate to an environment that will cause vaporization or dissipation of any excess carboxylic acids in the liquid metal carboxylate composition while the metal carboxylates are being converted to metal oxides.