| 摘要 |
Directly after leaving the last stand of the mill, the rod is subjected to a series of treatments above the Ms point. While the rod is still hot it is reheated to a temp. (I) equal to that of the nose of the time-temp.-transformation diagram for the steel rod, and held at (I) so all austenite is converted to sorbite. The steel is pref. first cooled to between Ms and 550 deg.C, so some sorbite forms, and is then reheated to 500-600 deg.C so the remaining austenite is transformed into sorbite. During cooling after leaving the mill, and before reheating, the steel is pref. between the Ar1 temp. and Ar1 + 50 deg.C. |
