| 摘要 |
PURPOSE: A method for producing a mild steel rod is provided to prevent red rust generation and to keep excellent scale property and mechanical property at the same time. CONSTITUTION: A low carbon billet contains less than 0.01wt% of C, less than 0.02wt% of Si, less than 0.15wt% of Mn, less than 0.015wt% of P, less than 0.015wt% of S and the remain of Fe and impurities. The billet is rolled to be a rod. The rolled rod is cooled with water at 250 to 500°C/sec and the cooled rod is wound in a temperature of 850 to 910°C. At an average cooling velocity of 7 to 11°C/sec, the cooled rod is first cooled down to 670°C, at an average cooling velocity of 3 to 6°C, secondly cooled down to 580°C and then cooled down to less than 580°C at an average cooling velocity of 7 to 13°C/sec. Thereby, the surface of the rod is prevented from generating red rust.
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