5th International Conference on Advances in Solidification Processes (ICASP-5) 5th International Symposium on Cutting Edge of Computer Simulation of Solidification, Casting and Refining (CSSCR-5)

During continuous casting of steel, the strand is exposed to severe thermal and mechanical stresses. These may trigger formation and growth of cracks, which deteriorate the slab properties. Particularly, at temperatures in the region of the second ductility trough, deformation can become critical. A low ductility level is often observed in a temperature range of 600°C to 1200°C, where the bending of the strand is commonly performed. One of the concepts for prevention of this problem is known as “Surface Structure Control Cooling” (SSCC). SSCC aims to intensively chill the external section of the strand just below the mould. In the present study, the SSCC heat treatment is compared with the regular cooling conditions for the concast strand. Hot tensile tests, which have been found very useful in assessing a steels susceptibility to cracking, are performed on a thermo-mechanical simulator. Both thermal histories are applied to microalloyed steel with variations of the test temperature and the results are summarized in hot ductility curves. Furthermore, the microstructures are investigated by optical microscopy and the precipitation states are studied by transmission electron microscopy (TEM).