近年来用户从降低原材料成本的观点出发,希望开发深冲加工性能优良的热轧钢板取代冷轧钢板。关于较薄的深冲用热轧钢板,以石川岛播磨公司为首的各钢铁厂从保证精轧温度这一点考虑,开发了低碳加硼钢板。并已投入工业生产。关于较厚的深冲用钢板,用冷轧法生产较困难,故强烈希望开发具有相当于或高于冷轧钢板深冲性能的热轧钢板。 In recent years, from the viewpoint of reducing the cost of raw materials, users are expected to develop hot-rolled steel sheets having excellent deep-drawing processability to replace cold-rolled steel sheets. Regarding the thinner hot-rolled steel sheet for deep drawing, each steel plant headed by Ishikawajima Broadcasting Co., Ltd. has developed a low-carbon boron-added steel sheet in consideration of the finish rolling temperature. And has been put into industrial production. With respect to thicker deep drawing steel plates, it is more difficult to produce them by the cold rolling method, so it is highly desirable to develop hot rolled steel plates having a deep drawability comparable to or higher than that of cold rolled steel plates.