Continuous Cooling Transformation of Deformed Austenite in Weathering Steel

The continuous cooling transformation(CCT) diagrams of deformed and undeformed austenite of weathering steel were constructed by means of a combined method of dilatometry and metallography.In the CCT diagram of deformed austenite,the transformation zone of ferrite is very wide,which provides a wide velocity window.Between the transformation zone of ferrite and bainite,there is a 60-80 ℃ metastable austenite zone,which provides a coiling window.Additionally,the transformation zone of bainite is sealed up at the right side.All these special features of the deformed austenite CCT diagram provide a basic condition for production of hot-rolled dual phase steel.