# US 2022/0339697 A1 · Composite powder with iron based particles coated with graphene material > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0339697 A1 - Document ID: US20220339697A1 - Status: Published application - Kind: A1 - Application number: 17/760,812 - Filed: 2020-09-17 - Published: 2022-10-27 - Earliest claimed: 2019-09-17 - Assignees: GraphMaTech AB - Applicants: GraphMaTech AB - Inventors: Ulf JANSSON; Simon TIDÉN; Mamoun TAHER; Luis DIAZ; Tommi REMONEN - Web page: https://patentgrep.com/patent/US20220339697A1 ## CPC - B22F 10/28: Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] - B22F 1/16: Metallic particles coated with a non-metal (coated with lubricating or binding agents or with organic material B22F1/10) - C01B 32/194: After-treatment - B22F 2301/35: Iron - B22F 2302/40: Carbon, graphite - B22F 2303/20: Coating by means of particles - B22F 2304/10: Micron size particles, i.e. above 1 micrometer up to 500 micrometer - B22F 2998/10: Processes characterised by the sequence of their steps - B22F 2999/00: Aspects linked to processes or compositions used in powder metallurgy - B33Y 70/10: Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials - B33Y 80/00: Products made by additive manufacturing - Y02P 10/25: Process efficiency - B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER - C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C} - B33Y: ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract The present invention relates to graphene coated iron based particles and a method of producing such. Provided is a composite powder suitable for powder metallurgy and additive manufacturing processes comprising particles of an iron based material with a coating of a graphene based material wherein the concentration of the graphene based material is between 0.1 wt % and 1.0 wt %. ## Claims ### Claim 1 A composite powder suitable for powder metallurgy and additive manufacturing processes, the composite powder comprising particles with a core of an iron based material and a coating of a graphene based material, wherein concentration of graphene based material is between 0.1 wt % and 1.0 wt %. ### Claim 2 (depends on 1) The composite powder according to claim 1, wherein the concentration of graphene based material is between 0.1 wt % and 0.95 wt %. ### Claim 3 (depends on 1) The composite powder according to claim 1, wherein the iron based material of the particles is pure iron. ### Claim 4 (depends on 1) The composite powder according to claim 1, wherein the iron based material of the particles is a stainless steel. ### Claim 5 (depends on 1) The composite powder according to claim 1, wherein the iron based material core has a size distribution wherein a majority of the particles is in the range of 1-100 μm. ### Claim 6 (depends on 5) The composite powder according to claim 5, wherein the iron based material core has a size distribution wherein a majority of the particles is in the range of 1-50 μm. ### Claim 7 (depends on 1) The composite powder according to claim 1, wherein the graphene based material of the coating is graphene oxide (GO). ### Claim 8 (depends on 1) The composite powder according to claim 1, wherein the graphene based material of the coating is a reduced graphene oxide (rGO). ### Claim 9 (depends on 1) The composite powder according to claim 1, wherein the graphene based material of the coating is a mixture of graphene oxide (GO) and reduced graphene oxide (rGO). ### Claim 10 A method of producing a composite powder suitable for powder metallurgy and additive manufacturing processes, the composite powder comprising particles of an iron based material with a coating of a graphene based material, the method comprising the steps of: providing an iron base metal powder with a known size distribution; providing a graphene based material in dispersion; diluting the graphene based material and adjusting the pH with addition of a basic substance, while recording the concentration of the graphene based material in the solution, wherein the pH is adjusted to be between 3 and 9; separating graphene agglomerates of the graphene material by sonication or agitation; dispersing the iron based metal powder in de-ionized water to create a slurry with predetermined iron based metal to water weight ratio; adding the graphene material dispersion to the iron based metal powder slurry in intervals or at a predetermined rate and mixing thoroughly for a predetermined time period; and drying the composite powder, wherein the amount of the added graphene material dispersion is adjusted so that the concentration of the graphene material in the dried composite powder is between 0.1 wt % and 1.0 wt %. ### Claim 11 (depends on 10) The method according to claim 10, wherein the amount of the added graphene material dispersion is selected so that the concentration of the graphene material is between 0.1 wt % and 0.95 wt %. ### Claim 12 (depends on 11) The method according to claim 11, wherein the amount of the added graphene material dispersion is selected so that the concentration of the graphene material is between 0.1 wt % and 0.5 wt %. ### Claim 13 (depends on 10) The method according to claim 10, wherein the iron based material of the particles comprises pure iron, and in the step of dilution and adjusting the pH, the pH is adjusted to be within 4-8. ### Claim 14 (depends on 10) The method according to claim 10, wherein the iron based material is stainless steel, and in the step of dilution and adjusting the pH, the pH is adjusted to be within 3-8. ### Claim 15 (depends on 10) The method according to claim 10, wherein, the iron based material of the particles comprises pure iron. ### Claim 16 (depends on 10) The method according to claim 10, wherein the iron based material of the particles is a stainless steel. ### Claim 17 (depends on 10) The method according to claim 10, wherein the graphene based material comprises graphene oxide (GO). ### Claim 18 (depends on 10) The method according to claim 10, wherein the graphene based material comprises reduced graphene oxide (rGO). ### Claim 19 (depends on 13) The method according to claim 13, wherein, in the step of dilution and adjusting the pH, the pH is adjusted to be within 5-7. ### Claim 20 (depends on 14) The method according to claim 14, wherein, in the step of dilution and adjusting the pH, the pH is adjusted to be within 4-7.