Metallurgically bonded wear resistant texture coatings for aluminum alloys and metal matrix composite electrode for producing same

Abstract

A coating process using a welding electrode comprises the steps of: electro-spark depositing a composite on to a substrate, wherein the composite consists essentially of alumina particles in a matrix, wherein the matrix is a metal selected from the group consisting of aluminum or an aluminum alloy. The substrate herein is an aluminum alloy. The coatings involve only aluminum and aluminum compounds, thereby intermetallic compound formation and galvanic corrosion of the coating-substrate materials system is avoided.

1 . A coating process, comprising the steps of:
 using an aluminum-aluminum oxide metal matrix composite electrode as a composite, electro-spark depositing said composite on to an aluminum alloy substrate to form a protective coating, wherein said protective coating consists of alumina particles in a matrix, wherein said matrix is a metal selected from the group consisting of aluminum and an aluminum alloy; and,   wherein said protective coating is metallurgically bonded as a continuous layer to an entire surface of said aluminum alloy substrate by electro-spark deposition, and wherein said composite material is formed without intermetallic compound formation between said protective coating and said aluminum alloy substrate.   
     
     
         2 . The coating process of  claim 1 , further comprising the step of forming a textured surface. 
     
     
         3 . The coating process of  claim 2 , further comprising the step of hard anodizing the textured surface.