METHOD FOR MANUFACTURING STEEL SHEET FOR COLD PRESS AND METHOD FOR MANUFACTURING PRESS COMPONENT

• Main Authors: MATSUKI Yuichi, NAKAGAWA Kinya, SHINMIYA Toyohisa
• Format: Patent
• Language: English; French; German
• Published: 11.05.2022
• Subjects: CHEMISTRY; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES,RIVETS, BOLTS OR WHEELS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; PERFORMING OPERATIONS; PUNCHING METAL; TRANSPORTING; WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS ORPROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL

Provided is a method that improves stretch flange formability of a steel sheet by individual treatment matching a material of the steel sheet without performing heat treatment in a die. This method is a method for manufacturing a steel sheet for cold press, and the steel sheet is manufactured by heating an edge of the steel sheet to a temperature within a heating temperature range preset according to a microstructure of the steel sheet, for example, a temperature within a heating temperature range of 500°C or more and 700°C or less in a case of a steel sheet the principal microstructure of which is composed of a single phase of martensite, and cooling the steel sheet. A region, within an edge of the steel sheet subjected to shearing in a shearing step, where it is estimated that a stretch flange crack is likely to occur when a press component is formed by cold pressing is determined, and a site to be heated and cooled is set within the region. By press-forming the manufactured steel sheet, a target press component is manufactured.