Abstract: Methods for coating a substrate with wear resistant particles by electroless nickel (Ni) plating. A method includes immersing the substrate in a bath provided in a cell, the bath having a Ni salt; adding cubic Boron Nitride (cBN) particles having a predetermined size to the bath so as to produce a predetermined concentration of cBN; maintaining the substrate in the bath with the cBN particles for a predetermined time; and removing the substrate, wherein the removed substrate has a coating of cBN and Ni in a first range.

Abstract: The present invention provides a method for preparing an electroless nickel coating composition that includes (a) coating a substrate with an electroless nickel coating to provide a coated substrate; and (b) subjecting the coated substrate to a heating protocol comprising heating to a temperature in a range from about 550° C. to about 700° C. for a period of from about 7 to about 30 hours. An article made from the method is also provided.

Abstract: The present invention provides a method for sealing pinholes in an electroless metal coating, said method comprising: (a) coating a substrate with an electroless metal coating layer to provide a coated article comprising an electroless metal coating in contact with the surface of the substrate, said electroless metal coating being characterized by the presence of pinhole imperfections which allow fluid communication between the substrate and the environment; (b) applying a layer of a curable epoxy sealant over the electroless metal coating layer and filling the pinhole imperfections; (c) curing the curable epoxy sealant to provide a cured epoxy overcoating layer; and (d) removing a substantial portion of the cured epoxy overcoating layer to provide an article comprising an electroless metal coating which is substantially free of pinhole imperfections allowing fluid communication between the substrate and the environment.

Abstract: Process for roughening a surface of a base metal substrate includes contacting the surface with an aqueous solution comprising oxalic acid, sulfuric acid, and hydrogen peroxide at a temperature and for a period of time effective to roughen the surface to an average roughness greater than 60 Ra, removing a modest amount of base material, and generating no narrow and deep crevices at all. The surface is roughened prior to application of an electroless coating onto the substrate.

Abstract: Multiple layers of nickel phosphorous coatings are formed by electroless plating onto a base metal substrate such as a turbine component. In one embodiment, a first nickel layer metallurgical bonded by a heat treatment process to a surface of the base metal substrate, the first nickel layer containing about 4 to about 6 weight percent phosphorous with the balance being essentially nickel; and a second nickel layer deposited onto the first layer, the second nickel layer containing about 8 to about 12 weight percent phosphorous with the balance being essentially nickel, wherein the first and second layers are formed by electroless plating. In this manner, adhesion is maximized without degrading the properties of the second layer such as corrosion resistance and ductility. Also disclosed are processes for forming the multilayered nickel phosphorus coatings.