Abstract��Effect of TMCP temperature parameters on the microstructure and mechanical properties of Nb-microalloyed steel was investigated. The following results be obtained. The finer grain can be obtained by two-stage controlled rolling and cooling compared with conventional rolling and rapid cooling. With increasing the cooling rate (10 to 23��/s), or decreasing the start temperature of finish rolling (780 to 605��) or lowering the final cooling temperature (930 to 850��), the grains size are refined, content of the mixed grains is aggravated, the strength increased and the plasticity decreased. The lower rolling temperature of finish rolling is helpful to improve the low temperature toughness. The mixed ferrite grains arise from mixed austenite grains which is due to inhomogeneous distribution of Nb(C,N) precipitates. Rolling with larger compression ratio (3.67) of coarse rolling can eliminate the mixed grains. The inheritance and aberrance of the mixed original austenite grains are significantly affected by the following temperature parameters. Applying these results to industrial production of high strength low alloyed structural steels for Hebei Puyang Iron & Steel Co., Ltd., making reasonable control rolling and control cooling process, the product properties meet the national standard requirement of GB/T 1591-94.
�ź��� �Ե��� ������ ��� ��ʤ��. �¶Ȳ��������Ͻ��ǿ�Ƚṹ����֯���ܵ�Ӱ��[J]. �й������ڿ���, 2010, 22(06): 35-35.
DU Hai-Jun De-Wen ZHAO Lin-Xiu Du LIU Xing-hua LIU Sheng-Guo ZHAO. Effect of Temperature Parameters on Microstructure and Mechanical Properties of Nb Micro-alloyed High Strength Structural Steel. Chinese Journal of Iron and Steel, 2010, 22(06): 35-35.
2010, Vol. 22 
