Li Q.-Q.,Valin Xiangtan Iron and Steel Co. |
Cao Z.-Q.,Valin Xiangtan Iron and Steel Co. |
Cao Z.-Q.,University of Science and Technology Beijing |
Li U.-L.,Valin Xiangtan Iron and Steel Co. |
And 4 more authors.
Jinshu Rechuli/Heat Treatment of Metals | Year: 2010
By thermal dilatometric change referencing microstructure and hardness examination, CCT diagrams of austenite with nondeformation and deformation for ultra-high strength steel were constructed in MMS-200 thermal mechanical simulator. Effects of deformation and cooling-rate on transformation behavior and microstructure of over-cooling austenite were studied. The result shows that 30% deformation at 850 °C induce transformation of ferrite and granular bainite(GB)at relative lower cooling rates (≤ °C/s)and expands the range of GB, while depresses transformation of lath bainite at higher cooling rates ( > 10 °C /s). With increasing cooling-rate, the microstructure evolves from polygonal ferrite( PF) + ( GB) to lath bainite( LB).