Patent ID: 8821988
Filing Date: 2014-09-02
Classification: C09D,C23C

Abstract:
1. A method for surface engineering a metal substrate, comprising the following steps: mixing at least two precursor constituents in powder form with a polymer binder to create a coating mix; coating the substrate with the coating mix; heating the substrate by electromagnetic induction, and controlling a frequency and duration of the heating to cause a reaction within the coating mix to create a desired mixture of ceramic or intermetallic constituents, evaporate the polymer binder, melt a portion of the substrate, and cause the ceramic or intermetallic constituents to mix with the substrate and form a compositionally graded surface modification region after the substrate re-solidifies, wherein the step of heating the substrate by electromagnetic induction is controlled such that the temperature of surface regions of the substrate is brought close to the melting temperature of the substrate but not high enough to cause the substrate to melt; wherein the reaction within the coating mix generates heat that supplies additional heat to the substrate to further raise the temperature of the substrate such that a portion of the substrate melts; wherein the mixing of the ceramic or intermetallic constituents with the molten portion of the substrate occurs via induced eddy currents from the induction heating; wherein upon removal of a source of the electromagnetic induction heating, the molten portion of the substrate resolidifies; wherein the ceramic or intermetallic constituents are redistributed within the resolidified substrate at decreasing percentages along a depth of the substrate so that the ceramic or intermetallic constituents vary from 100% at a surface of the substrate to 0% at a defined depth of the substrate, and wherein the step of controlling the frequency includes adjusting the frequency to adjust a depth of the modification region, wherein a higher frequency leads to a smaller depth of the modification region.