# US 11,998,971 B2 · Hot press-formed part, and manufacturing method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,998,971 B2 - Document ID: US11998971B2 - Status: Granted - Kind: B2 - Application number: 18/123,460 - Filed: 2023-03-20 - Published: 2023-07-20 - Granted: 2024-06-04 - Earliest claimed: 2018-11-30 - Assignees: Posco - Applicants: Posco Co., Ltd - Inventors: Seong-Woo Kim; Jin-Keun Oh; Sang-Heon Kim; Hyo-Sik Chun - Web page: https://patentgrep.com/patent/US11998971B2 ## CPC - B21D 35/007: {Layered blanks (B21D22/203 takes precedence; joining superposed plates B21D39/031, B21D39/034, B21D39/035)} - B32B 15/012: {one layer being formed of an iron alloy or steel, another layer being formed of aluminium or an aluminium alloy} - C21D 1/26: Methods of annealing - C21D 1/673: for die quenching - C21D 6/002: {containing Cr (C21D6/004 takes precedence)} - C21D 6/005: {containing Mn} - C21D 6/008: {containing Si} - C21D 8/00: Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment (hardening articles or materials formed by forging or rolling with no further heating beyond that required for the formation C21D1/02) - C21D 8/0252: {with application of tension} - C21D 8/0447: {characterised by the heat treatment} - C21D 9/0068: {for particular articles not mentioned below} - C21D 9/46: for sheet metals - C21D 9/48: deep-drawing sheets - C22C 38/002: {containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60} - C22C 38/02: containing silicon - C22C 38/04: containing manganese - C22C 38/06: containing aluminium - C22C 38/18: containing chromium - C22C 38/28: with titanium or zirconium - C22C 38/32: with boron - C23C 2/12: Aluminium or alloys based thereon - C23C 2/26: After-treatment (C23C2/14 takes precedence) - C23C 2/28: Thermal after-treatment, e.g. treatment in oil bath - C23C 2/29: {Cooling or quenching} - C23C 2/40: Plates; Strips - C23C 28/02: only coatings {only including layers} of metallic material - C23C 28/021: {including at least one metal alloy layer} - C23C 28/023: {only coatings of metal elements only} - B21D 22/022: {by heating the blank or stamping associated with heat treatment (C21D takes precedence)} - B21D 35/005: {characterized by the material of the blank or the workpiece (B21D26/053 takes precedence)} - B21D: WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL (working or processing of wire B21F) - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - C21D: MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING (surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by this subclass C23F17/00; unidirectional solidification of eutectic materials or unidirectional demixing of eutectoid materials C30B) - C22C: ALLOYS (treatment of alloys C21D, C22F) - 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 The present disclosure provides a hot-press formed part comprising a plated steel sheet and an aluminum alloy plated layer formed on the plated steel sheet, wherein the aluminum alloy plated layer comprises: an alloying layer (I) formed on the plated steel sheet and containing, by weight %, 5-30% of Al; an alloying layer (II) formed on the alloying layer (I) and containing, by weight %, 30 to 60% of Al; an alloying layer (III) formed on the alloying layer (II) and containing, by weight %, 20-50% of Al and 5-20% of Si; and an alloying layer (IV) formed continuously or discontinuously on at least a part of the surface of the alloying layer (III), and containing 30-60% of Al, wherein the rate of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer is 10% or more. ## Claims ### Claim 1 A hot-press formed member, comprising: a base steel sheet; and an aluminum alloy plated layer on the base steel sheet, wherein the aluminum alloy plated layer comprises: an alloying layer (I) on the base steel sheet and comprising, by weight %, 5-30% of Al, 0-10% of Si, and a balance of Fe and inevitable impurities; an alloying layer (II) on the alloying layer (I) and comprising, by weight %, 30-60% of Al, 0-5% of Si, and a balance of Fe and inevitable impurities; an alloying layer (III) on the alloying layer (II) and comprising, by weight %, 20-50% of Al, 5-20% of Si, and a balance of Fe and inevitable impurities; and an alloying layer (IV) on the alloying layer (III) and comprising, by weight, 30-60% of Al, 0-5% of Si, and a balance of Fe and inevitable impurities, and wherein a ratio of the alloying layer (III) exposed on an outermost surface of the aluminum alloy plated layer is 10% or more. ### Claim 2 (depends on 1) The hot-press formed member of claim 1, wherein the ratio of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer is 15% or more. ### Claim 3 (depends on 1) The hot-press formed member of claim 1, wherein the ratio of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer is 20% or more. ### Claim 4 (depends on 1) The hot-press formed member of claim 1, wherein the alloying layer (III) comprises a plurality of pores. ### Claim 5 (depends on 4) The hot-press formed member of claim 4, wherein a ratio the plurality of pores of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer is 5-50%. ### Claim 6 (depends on 5) The hot-press formed member of claim 5, wherein a ratio the plurality of pores of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer is 7-50%. ### Claim 7 (depends on 1) The hot-press formed member of claim 1, wherein the alloying layer (IV) comprises a plurality of pores. ### Claim 8 (depends on 7) The hot-press formed member of claim 7, wherein a number of the plurality of pores of the alloying layer (IV) is more than a number of the plurality of pores of alloying layer (III). ### Claim 9 (depends on 1) The hot-press formed member of claim 1, wherein the base steel sheet comprises, by weight %, 0.04-0.5% of C, 0.01-2% of Si, 0.1-5% of Mn, 0.001-0.05% of P, 0.0001-0.02% of S, 0.001-1% of Al, 0.001-0.02% of N, and optionally comprising one or more of 0.001-0.01% of B, 0.01-1% of Cr, and 0.001-0.2% of Ti, and a balance Fe and other impurities. ### Claim 10 (depends on 1) The hot-press formed member of claim 1, wherein the ratio of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer is an average occupancy ratio of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer. ### Claim 11 A hot-press formed member, comprising: a base steel sheet; and an aluminum alloy plated portion on the base steel sheet, wherein the aluminum alloy plated portion comprises: an alloying portion (I) on the base steel sheet and comprising, by weight %, 5-30% of Al, 0-10% of Si, and a balance of Fe and inevitable impurities; an alloying portion (II) on the alloying portion (I) and comprising, by weight %, 30-60% of Al, 0-5% of Si, and a balance of Fe and inevitable impurities; an alloying portion (III) on the alloying portion (II) and comprising, by weight %, 20-50% of Al, 5-20% of Si, and a balance of Fe and inevitable impurities; and an alloying portion (IV) on the alloying portion (III) and comprising, by weight, 30-60% of Al, 0-5% of Si, and a balance of Fe and inevitable impurities, and wherein a ratio of the alloying portion (III) exposed on an outermost surface of the aluminum alloy plated portion is 10% or more. ### Claim 12 (depends on 11) The hot-press formed member of claim 11, wherein the ratio of the alloying portion (III) exposed on the outermost surface of the aluminum alloy plated portion is 15% or more. ### Claim 13 (depends on 11) The hot-press formed member of claim 11, wherein the ratio of the alloying portion (III) exposed on the outermost surface of the aluminum alloy plated portion is 20% or more. ### Claim 14 (depends on 11) The hot-press formed member of claim 11, wherein the alloying portion (III) exposed on the outermost surface of the portion of the aluminum alloy plated portion comprises a plurality of pores. ### Claim 15 (depends on 14) The hot-press formed member of claim 14, wherein a ratio the plurality of pores of the alloying portion (III) exposed on the outermost surface of the aluminum alloy plated portion is 5-50%. ### Claim 16 (depends on 14) The hot-press formed member of claim 14, wherein a ratio the plurality of pores of the alloying portion (III) exposed on the outermost surface of the aluminum alloy plated portion is 7-50%. ### Claim 17 (depends on 11) The hot-press formed member of claim 11, wherein the alloying portion (IV) comprises a plurality of pores. ### Claim 18 (depends on 11) The hot-press formed member of claim 11, wherein a number of the pores of the alloying portion (IV) is more than a number of the pores of the alloying portion (III). ### Claim 19 (depends on 11) The hot-press formed member of claim 11, wherein the base steel sheet comprises, by weight %, 0.04-0.5% of C, 0.01-2% of Si, 0.1-5% of Mn, 0.001-0.05% of P, 0.0001-0.02% of S, 0.001-1% of Al, 0.001-0.02% of N, and optionally comprising one or more of 0.001-0.01% of B, 0.01-1% of Cr, and 0.001-0.2% of Ti, and a balance Fe and other impurities. ### Claim 20 (depends on 11) The hot-press formed member of claim 11, wherein the ratio of the alloying portion (III) exposed on the outermost surface of the aluminum alloy plated portion is an average occupancy ratio of the alloying portion (III) exposed on the outermost surface of the aluminum alloy plated portion.