Abstract: Disclosed is an improved abrasive material particularly useful as a dispersoid in metal matrices to provide articles of use having superior abrasive properties, especially at elevated temperatures. The improved abrasive material typically comprises silicon carbide particulate, the individual particles of which have a predominantly alumina coating thereon to inhibit dissolution of the particles in the metal matrix at high temperatures. The invention finds special application in abrasive blade tips for service in gas turbine engines, the tips comprising a nickel base or cobalt base superalloy having the alumina coated silicon carbide particles dispersed therein.

Abstract: A method for fabricating a gas turbine engine disk by co-extrusion is described which comprises the steps of preparing a cylindrical shaped preform billet having a central bore region of preselected radius r and comprising a first material, and a rim region surrounding the bore region to a radius R of the preform billet and comprising a second material, extruding the preform billet at preselected extrusion temperature through an extrusion die to form an extrusion product of preselected reduction, and removing the disk from the extrusion product.