| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that in a conventional method for producing a blued metal strip, the control of the thickness of an oxide film is difficult because of the variation of oxide film formation due to a change in a treatment temperature because the dew point of an atmospheric gas is in the range suitable for the formation of the oxide film also during the heating period and the in-furnace cooling period in each of which the treating temperature changes. <P>SOLUTION: According to the method for producing the blued metal strip, the feed of steam into a heat treatment furnace in performing the heat treatment of an open coil is controlled so that the dew point of an atmospheric gas becomes the lower limit or higher in a predetermined dew point range only during the constant-temperature heating period. <P>COPYRIGHT: (C)2012,JPO&INPIT |
