To provide a manufacturing method of a cold-rolled steel plate excellent in sliding characteristic and die galling resistance, and to provide the cold-rolled steel plate.
After executing the hot rolling and the cold rolling, the oxidation treatment is executed by a direct-firing burner, and successively reduction treatment is executed in the atmosphere containing 1.0-100% H2. Fe-based oxides are formed on a surface by executing the oxidation treatment. Thereafter, by reducing the oxides, a cold-rolled steel plate is obtained, wherein reduced Fe is present on its surface. In the oxidation treatment, the steel plate is preferably heated to 400-900C, and the steel plate is further heated at the temperature elevation rate of 5C/sec in the temperature range of 400-650C.
HOSHINO KATSUYA
Kazuhiro Mori
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