ժҪ The expansion curves of continuous cooling transformation at different cooling rates was determined for U75V rail steel by THERMECMASTOR- Z thermal simulator��and continuous cooling transformation curve was obtained.The influedce of cooling rate on microstructure and hardness was studied.On the other hand��the softening behavior of isothermal deforming at austenite area 850��1000�� within interval of passes has been also studied by double-pass compression test.The results show that the product of austenite transformation was pearlite when the cooling rate was lower than 10��.Troostite and martensite were gained at the cooling rate of 10��•s-1. Only martensite was received when the cooling rate was in the range of 10�� 50��•s-1.the hardness of steel increased with the increase of cooling rate.Results also indicated that 30% deformation and 3S-1 deforming rate��as deformation temperature ��1000�棬relaxation time for performing recrystallization was��100s��and as deformation temperature��880 �棬it was difficult even extending relaxation time to put forward recrystallization of steel.
Abstract��The expansion curves of continuous cooling transformation at different cooling rates was determined for U75V rail steel by THERMECMASTOR- Z thermal simulator��and continuous cooling transformation curve was obtained.The influedce of cooling rate on microstructure and hardness was studied.On the other hand��the softening behavior of isothermal deforming at austenite area 850��1000�� within interval of passes has been also studied by double-pass compression test.The results show that the product of austenite transformation was pearlite when the cooling rate was lower than 10��.Troostite and martensite were gained at the cooling rate of 10��•s-1. Only martensite was received when the cooling rate was in the range of 10�� 50��•s-1.the hardness of steel increased with the increase of cooling rate.Results also indicated that 30% deformation and 3S-1 deforming rate��as deformation temperature ��1000�棬relaxation time for performing recrystallization was��100s��and as deformation temperature��880 �棬it was difficult even extending relaxation time to put forward recrystallization of steel.
REN An-chao;JI Yu;ZHOU Gui-feng;et al. Hot Deformation Behavior of V-microalloyed Steel[J]. �й������ڿ���, 2010, 17(8): 55-60.
REN An-chao;JI Yu;ZHOU Gui-feng;et al. ���Ͻ���ȱ�����Ϊ. Chinese Journal of Iron and Steel, 2010, 17(8): 55-60.
2010, Vol. 17 
