Abstract：High temperature mechanical behaviors of Nb and Nb、Ti containing steel were tested by Gleeble1500 thermal simulation testing machine. Meanwhile, influences of precipitate, phase change, cooling rate and dynamic recrystallization on hot ductility of the micro-alloy steel were also analyzed utilizing Gleeble. The results demonstrate that: the embrittlement region Ⅱ does not exist in Nb nor Nb、Ti containing steel. The temperature range of ductility region Ⅲ is about 950～700℃ in Nb containing steel and 900～725℃ in Nb、Ti containing steel respectively. Precipitation along the grain boundaries and during γ→α phase transformation are main factors which lead to a decrease on hot ductility of Nb and Nb、Ti containing steel. In the practice process the incidence of surface micro-cracks in micro-alloying steel can be reduced dramatically by decreasing specific water rate in secondary cooling zone.
龚雅林. 中碳微合金化钢高温延塑性的研究[J]. 钢铁, 2010, 45(6): 67-67.
gong ya-lin. Research on hot ductility of Medium carbon microalloyed steel. Iron and Steel, 2010, 45(6): 67-67.
2010, Vol. 45 
