Process and composition for formation of hybrid aluminum composite coating
View Patent ↗Process for formation of composite coatings and composite coatings formed thereby. A process for formation of a metal-matrix composite coating on a surface of a substrate is provided. The substrate is an aluminum alloy. The metal-matrix composite coating is formed on the substrate through laser deposition using filler materials comprising aluminum, silicon and graphite. The particles forming the metal-matrix composite coating are formed in-situ from the filler materials. A metal-matrix composite coating obtained by the laser deposition process with in-situ formation of particles is also provided.
1. A process for formation of a metal-matrix composite coating on a surface of a substrate, the method comprising:
a) melting a first portion of said surface of said substrate with a high-energy power source to form a melt pool in a melt zone;
b) feeding filler materials into the melt zone, wherein said filler materials comprises aluminum powder, silicon powder and graphite powder;
c) subjecting the melt zone and filler materials to the high-energy power source to allow for an in-situ reaction and formation of a solid deposit on said first portion of said surface of said substrate; and
d) repeating steps a) to c) on multiple adjacent portions of said surface of said substrate to provide a continuous layer of the solid deposit thereby forming the metal-matrix composite coating,
wherein the filler materials have a following composition ratio by mole fraction:
aluminum from about 30% to about 65%;
silicon from about 20% to about 50%; and
graphite from about 10% to about 30%.
2. The process of claim 1 , wherein the substrate is an aluminum alloy.
3. The process of claim 1 , wherein the high-energy source is a laser.
4. The process of claim 1 , wherein the filler materials are mixed prior to feeding said filler materials into the melt zone.
5. The process of claim 1 , wherein the filler materials are fed through at least one feeding nozzle.
6. The process of claim 1 , wherein the filler materials are each fed through separate inlets of a feeding nozzle.
7. The process of claim 1 , wherein the in-situ reaction in step c) provides formation of SiC particles and Al4SiC4 plates.
8. The process of claim 7 , wherein the SiC particles and Al4SiC4 plates provide reinforcements for an aluminum matrix to form the solid deposit.
9. The process of claim 1 , further comprising repeating steps a) to d) to form a second layer on top of the continuous layer.
10. The process of claim 1 , further comprising repeating steps a) to d) multiple times to form multiple layers on top of the continuous layer.