Patent ID: 7179507

Claim:
A method of providing a three-phase abradable seal on a substrate comprising applying an adherent coating having a thickness of up to 3 mm to the substrate by thermally spraying a composition thereon comprising 5 to 60 wt % total of a solid lubricant and a ceramic in a ratio of 1:7 to 20:1 by weight of solid lubricant to ceramic, the balance a matrix-forming metal or metal alloy, wherein the solid lubricant is hexagonal boron nitride, wherein the matrix-forming metal or metal alloy is Cu, Al or an alloy of Cu, Al, CuAl or AlSi, and wherein the ceramic is at least one material selected from the group consisting of albite, illite, and quartz particles, and mixtures thereof, and alumina-silica-based ceramic.