| 摘要 |
PROBLEM TO BE SOLVED: To provide a hot-dip galvannealed steel sheet having a uniform distribution both of a plated weight and an alloyed degree in a widthwise direction, and a superior plating performance, and to provide a manufacturing method therefor. SOLUTION: The method for manufacturing the hot-dip galvannealed steel sheet comprises individually arranging an electromagnet 5 for exerting a magnetic force on the direction of intersecting with the surface of the steel sheet above a gas throttle device 4, and a device 12 for measuring the alloyed degree of a plated film after alloying treatment, downstream of an alloying furnace 8; controlling a value of an electric current in the electromagnet 5 in order to uniformize the distribution of the alloyed degree of the plated film in the widthwise direction, which is measured with the device 12 for measuring the alloyed degree; controlling an output of the alloying furnace 8 in order to match the value of the alloyed degree to a desired value; and controlling the gas throttle device 4 in order to match the plated weight measured with a device 11 for measuring the plated weight to a desired value. The hot-dip galvannealed steel sheet thus manufactured has the uniform distribution both of the plated weight and the alloyed degree in the widthwise direction. COPYRIGHT: (C)2004,JPO
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