# US 9,517,521 B2 · Method for repairing component > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,517,521 B2 - Document ID: US9517521B2 - Status: Granted - Kind: B2 - Application number: 13/934,541 - Filed: 2013-07-03 - Published: 2014-01-09 - Granted: 2016-12-13 - Earliest claimed: 2012-07-05 - Assignees: General Electric Company - Applicants: Mayank Tiwari; Laurent Cretegny; Yong Liu; Bala Srinivasan Parthasarathy; Ravi Agrawal; Yong Wu - Inventors: Mayank Tiwari; Laurent Cretegny; Yong Liu; Bala Srinivasan Parthasarathy; Ravi Agrawal; Yong Wu - Web page: https://patentgrep.com/patent/US9517521B2 ## CPC - B23K 9/04: Welding for other purposes than joining, e.g. built-up welding - B23P 6/00: Restoring or reconditioning objects (straightening or restoring form of sheet metal, metal rods, metal tubes, metal profiles, or specific articles made therefrom B21D1/00, B21D3/00; repairing defective or damaged objects by casting techniques B22D19/10) - C23C 24/106: {Coating with metal alloys or metal elements only} - B23K: SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM - B23P: METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS (arrangements for copying or controlling B23Q) - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) ## Abstract A method for repairing a component is provided. The method comprises: tracing an electrode across a defect/damage on the component at a preselected distance from the component; feeding a first metal powder and a second metal powder into a discharging gap between the electrode and the component; controlling feed rates of the first and second metal powders separately; and electro-spark depositing the first and second metal powders to the component to form a hybrid metal coating. The first metal powder comprises a first metal or alloy with a Vickers hardness rating of about 70-200% of the Vickers hardness rating of the component. The second metal powder comprises a second metal or alloy having lubricating/anti-corrosion properties. ## Claims ### Claim 1 A method for repairing a component, comprising: tracing a non-consumable electrode across a defect/damage on the component at a preselected distance from the component; feeding a first metal powder and a second metal powder into a discharging gap between the electrode and the component, wherein the first metal powder comprises a first metal or alloy with a Vickers hardness rating of about 70-200% of the Vickers hardness rating of the component and wherein the second metal powder comprises a second metal or alloy having lubricating/anti-corrosion properties; controlling feed rates of the first and second metal powders separately; micro-spark depositing the first metal powder to the component to form a first metal coating layer from the first metal powder; and tracing the electrode back over the first metal coating layer and micro-spark depositing the second metal powder over the first metal coating layer to form a second metal coating from the second metal powder overlying the first metal coating layer, the first and second metal coating layers defining a hybrid metal coating. ### Claim 2 (depends on 1) The method of claim 1, further comprises: examining a surface of the component to identify the location of the defect/damage before tracing the electrode across the defect/damage. ### Claim 3 (depends on 1) The method of claim 1, wherein the first metal powder is primarily located within interstitial spaces of the defect/damage as the first metal coating layer and the second metal powder is deposited as a surface layer above the first metal coating layer. ### Claim 4 (depends on 3) The method of claim 3, wherein the first metal coating layer has a thickness of about 30 microns. ### Claim 5 (depends on 3) The method of claim 3, wherein the surface layer has a thickness of about 10 microns. ### Claim 6 (depends on 3) The method of claim 3, wherein a transition layer is deposited between the first metal coating layer and the surface layer. ### Claim 7 (depends on 6) The method of claim 6, wherein the transition layer is a graded layer with a compositional gradient of the first metal powder and the second metal powder. ### Claim 8 (depends on 6) The method of claim 6, wherein the transition layer is a graded layer, in which the content of the first metal or alloy decreases whereas the content of the second metal or alloy increases along a direction from the first metal coating layer to the surface layer. ### Claim 9 (depends on 6) The method of claim 6, wherein the hybrid metal coating is formed by: depositing the first metal powder to the interstitial spaces of the defect/damage to form the first metal coating layer; depositing the first and second metal powders onto the first metal coating layer to form a graded transition layer, while increasing the feed rate of the second metal powder and reducing the feed rate of the first metal powder; and depositing the second metal powder to the transition layer to form the surface layer. ### Claim 10 (depends on 6) The method of claim 6, wherein the transition layer is formed by a metal powder comprising a metal or alloy adhesion bond compatible with but different from both the first metal or alloy and the second metal or alloy. ### Claim 11 (depends on 1) The method of claim 1, wherein the first metal or alloy has a Vickers hardness rating of about 90-200% of the Vickers hardness rating of the component. ### Claim 12 (depends on 1) The method of claim 1, wherein the first metal or alloy has a Brinell hardness rating of about 95-200% of the Vickers hardness rating of the component. ### Claim 13 (depends on 1) The method of claim 1, wherein the first metal or alloy has a Brinell hardness rating of about 95-150% of the Vickers hardness rating of the component. ### Claim 14 (depends on 1) The method of claim 1, wherein the first metal or alloy has a composition the same with that of the component. ### Claim 15 (depends on 1) The method of claim 1, wherein the second metal or alloy is able to provide a friction coefficient value of about 0.05-0.1under sliding or rolling-sliding boundary lubrication conditions at a temperature less than about 100° C. ### Claim 16 (depends on 1) The method of claim 1, wherein the second metal or alloy is more corrosion resistant than the base component. ### Claim 17 (depends on 1) The method of claim 1, wherein the second metal or alloy comprises copper, silver, tin, zinc, lead, nickel based alloy, or a combination thereof. ### Claim 18 (depends on 1) The method of claim 1, wherein the first and second metal powders are fed into the discharging gap through a powder feeding channel within the electrode. ### Claim 19 (depends on 18) The method of claim 18, wherein the first and second metal powders are introduced into the powder feeding channel via two powder feeders separately. ### Claim 20 (depends on 1) The method of claim 1, wherein the first and second metal powders are fed into the discharging gap through two nozzles separately.