METHOD FOR REDUCING EDGE SERRATION DEFECTS IN THIN SLABS

摘要

In the present invention, a thin slab having an alloy composition comprising carbon (C), niobium (Nb) and aluminium (Al) and a remainder of iron (Fe) and unavoidable impurities is reheated in a heat-treatment furnace where it is homogenised to an austenitic structure, and the production of precipitates is controlled by maintaining the heat-treatment-furnace extraction temperature of the thin slab at no lower than the NbC precipitation temperature and no higher than the AlN precipitation temperature, and then hot rolling is carried out. The present invention is advantageous in that it improves productivity since edge serration defects in thin slabs are reduced by controlling the heat-treatment-furnace extraction temperature of thin slabs.