# US 2017/0282501 A1 · Steel for carburizing, carburized steel component, and method of producing the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0282501 A1 - Document ID: US20170282501A1 - Status: Published application - Kind: A1 - Application number: 15/622,712 - Filed: 2017-06-14 - Published: 2017-10-05 - Earliest claimed: 2011-02-10 - Assignees: Nippon Steel & Sumitomo Metal Corporation - Applicants: Nippon Steel & Sumitomo Metal Corporation - Inventors: Manabu KUBOTA - Web page: https://patentgrep.com/patent/US20170282501A1 ## CPC - B32B 15/04: comprising metal as the main or only constituent of a layer, {which is} next to another layer of {the same or of} a {different material (next to a bituminous or tarry layer B32B11/08; next to a water-setting substance layer B32B13/06; next to a glass layer B32B17/061; next to a cellulosic plastic layer B32B23/042)} - C21D 1/06: Surface hardening - C21D 1/32: Soft annealing, e.g. spheroidising - 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 8/06: during manufacturing of rods or wires - C21D 9/32: for gear wheels, worm wheels, or the like - C22C 38/001: {containing N} - C22C 38/002: {containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60} - C22C 38/005: {containing rare earths, i.e. Sc, Y, Lanthanides} - C22C 38/02: containing silicon - C22C 38/04: containing manganese - C22C 38/06: containing aluminium - C22C 38/18: containing chromium - C22C 38/22: with molybdenum or tungsten - C22C 38/24: with vanadium - C22C 38/26: with niobium or tantalum - C22C 38/28: with titanium or zirconium - C22C 38/32: with boron - C22C 38/42: with copper - C22C 38/44: with molybdenum or tungsten - C22C 38/48: with niobium or tantalum - C22C 38/60: containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur - C23C 8/02: Pretreatment of the material to be coated (C23C8/04 takes precedence) - C23C 8/22: of ferrous surfaces - C23C 8/32: of ferrous surfaces - C23C 8/80: After-treatment - C21D 1/25: Hardening, combined with annealing between 300 degrees Celsius and 600 degrees Celsius, i.e. heat refining ("Vergüten") - C21D 2211/002: Bainite - C21D 2211/003: Cementite - C21D 2211/004: Dispersions; Precipitations - C21D 2211/005: Ferrite - C21D 2211/009: Pearlite - 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 A steel for a carburizing and a carburized steel component having a steel portion and a carburized layer with a thickness of more than 0.4 mm to less than 2 mm which is formed on an outside of the steel portion. A chemical composition of the steel for the carburizing and the steel portion of the carburized steel component satisfies simultaneously equations of a hardness parameter, a hardenability parameter, and an AlN precipitation parameter. ## Claims ### Claim 1 A steel for a carburizing comprising as a chemical composition, by mass %, C: 0.07% to 0.13%, Si: 0.0001% to 0.50%, Mn: 0.0001% to 0.80%, S: 0.0001% to 0.100%, Cr: more than 1.30% to 5.00%, B: 0.0005% to 0.0100%, Al: 0.105% to 0.200%, N: 0.0030% to 0.0100%, Ti: limited to 0.020% or less, P: limited to 0.050% or less, O: limited to 0.0030% or less, and a balance consisting of iron and unavoidable impurities, wherein: amounts expressed in mass % of each element in the chemical composition satisfy simultaneously a following Equation 1 as a hardness parameter, a following Equation 2 as a hardenability parameter, and a following Equation 3 as an AlN precipitation parameter; a shape is a bar or a wire rod in which a cross section perpendicular to a longitudinal direction is round; and when a distance from a periphery to a center of the cross section is defined as r in unit of mm, in a metallographic structure of a surface layer which is a portion from the periphery to r×0.01, a ferrite and a pearlite are limited, by area %, to 10% or less in total, and a balance includes at least one of martensite, bainite, tempered martensite, tempered bainite, and cementites, 0.10