SHEARING PART HARDENING METHOD, STEEL MATERIAL HAVING HARDENED SHEARING PART, AND MANUFACTURING METHOD FOR STEEL MATERIAL HAVING HARDENED SHEARING PART

• Main Author: YAMANAKA SAYO
• Format: Patent
• Language: English; Japanese
• Published: 25.07.2016
• 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

PROBLEM TO BE SOLVED: To provide a shearing part hardening method for excellently hardening a shearing part formed in a steel material even if a DI value of the steel material is low.SOLUTION: A shearing part hardening method includes: a heating step of heating a steel material so as to raise a temperature of the steel material to a temperature equal to or more than an austenitizing temperature; a shearing step of shearing the steel material while keeping a temperature of the steel material heated in the heating step in a temperature equal to or more than an austenitizing temperature so as to form a shearing part on the steel material; and a cooling step of cooling the steel material so as to lower a temperature of the steel material formed with the shearing part in the shearing step to a temperature equal to or less than a martensite point.SELECTED DRAWING: Figure 11 【課題】 鋼材のＤＩ値が低くても、その鋼材に形成されている剪断加工部が良好に焼入れされるような、剪断加工部の焼入れ方法を提供すること。【解決手段】 鋼材の温度がオーステナイト化温度以上の温度にまで上昇するように、鋼材を加熱する加熱工程と、加熱工程にて加熱された鋼材の温度をオーステナイト化温度以上の温度に維持したまま鋼材を剪断加工して、鋼材に剪断加工部を形成する剪断加工工程と、剪断加工工程にて剪断加工部が形成された鋼材の温度がマルテンサイト点以下の温度にまで低下するように、鋼材を冷却する冷却工程と、を含む、剪断加工部の焼入れ方法とすること。【選択図】 図１１