PRODUCTION METHOD OF STEEL SHEET FOR PRESS, MANUFACTURING METHOD OF PRESSED COMPONENT, STEEL SHEET, AND EVALUATION METHOD FOR FORMABILITY OF STRETCH FLANGE

• Main Authors: MATSUKI YUICHI, NAKAGAWA KINYA, SHINGU TOYOHISA, YAMAZAKI YUJI
• Format: Patent
• Language: English; Japanese
• Published: 16.09.2021
• Subjects: CHEMISTRY; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; 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

To further suppress cracking of an elongation flange part by setting a more appropriate heating treatment temperature and heating range according to a steel material.SOLUTION: There is provided a method for manufacturing a steel sheet for press to be subjected to press working. The method includes a shearing process 10A for applying shearing work to at least a part of the end of a steel plate, and a heating process 10B for heating a preset heating range from the end of at least a part of the end of the shearing steel plate. The method includes: a ductility estimation step 10C of estimating a change in ductility of a heated part by setting the heating temperature of the heating process 10B at 600°C or more and less than 800°C and further heating under the same heating conditions as in the heating step 10B; and a heating range determination step 10D of setting a heating range to a range of 3 mm or more from an end face when ductility is estimated to be improved, and setting a heating range to a range of 6 mm or less from the end face when ductility is estimated to be lowered, based on the estimation in the ductility estimation step 10C.SELECTED DRAWING: Figure 5 【課題】鋼材に応じたより適切な加熱処理温度及び加熱範囲を設定して、伸びフランジ部の割れをより抑制可能とする。【解決手段】プレス加工が施されるプレス用鋼板の製造方法である。鋼板の少なくとも一部の端部にせん断加工を施すせん断工程１０Ａと、せん断加工を施した鋼板の端部の少なくとも一部の端部について当該端部から予め設定した加熱範囲を加熱する加熱工程１０Ｂとを備える。加熱工程１０Ｂでの加熱温度を６００℃以上８００℃未満とし、更に、加熱工程１０Ｂと同じ加熱条件で加熱することで、加熱部の延性の変化を推定する延性推定工程１０Ｃと、延性推定工程１０Ｃの推定に基づき、延性が向上すると推定した場合には加熱範囲を端面から３ｍｍ以上の範囲とし、延性が低下すると推定した場合には加熱範囲を端面から６ｍｍ以内の範囲とする加熱範囲決定工程１０Ｄと、を有する。【選択図】 図５