Transformation Microstructure Evolution Rules of High Strength Weathering Steel

Composition design and smelting of 400MPa high strength weathering steel were carried out in laboratory.On the basis of thermal simulation experiment of slab,evolution rules of austenitic microstructure under different process conditions were analyzed.Static and dynamic CCT curves of the experimental steel were tested further,and the phase transformation rules were investigated.The transformation temperature of dynamic CCT was higher than that of static CCT,and temperature range of γ+α critical zone of dynamic CCT was over 100℃ while that of static CCT was in the range of 70-90℃;the microstructure consisted of a amount of ferrite and partial pearlite.