Particulate corrosion resistant coating composition

Abstract

A composition comprising a glass-forming binder component and a particulate corrosion resistant component. The particulate corrosion resistant component comprises corrosion resistant particulates having: a CTEof at least about 4 and being solid at a temperature of about 1300° F. (704° C.) or greater; and a maximum median particle size defined by one of the following formulas: (a) for a CTEof 8 or less, an MP equal to or less than (4.375×CTE)−10; and (b) for a CTEp of greater than 8, an Mequal to or less than (−4.375×CTE)+60, wherein CTEis the average CTE of the corrosion resistant particulates and wherein Mis the median equivalent spherical diameter (ESD), in microns, of the corrosion resistant particulates. Also disclosed is an article comprising a turbine component comprising a metal substrate and a corrosion resistant coating overlaying the metal substrate, as well as a method for forming at least one layer of the corrosion resistant coating adjacent to the metal substrate. The corrosion resistant coating has a maximum thickness defined by one of the following formulas: (3) for a CTEof 8 or less, an Tequal to or less than (1.5×CTE)−3.5; and (4) for a CTEof greater than 8, an Tequal to or less than (−1.5×CTE)+20.5, wherein Tis the thickness, in mils, of the corrosion resistant coating.