杨维宇, 张凤明, 李智丽, et al. Microstructure Transformation and Properties of a 1200 MPa New Type Nb-V Micro-Alloying Bainite Rail Steel[J]. Special Steel, 2020, 41(5): 48-51.
杨维宇, 张凤明, 李智丽, et al. Microstructure Transformation and Properties of a 1200 MPa New Type Nb-V Micro-Alloying Bainite Rail Steel[J]. Special Steel, 2020, 41(5): 48-51.DOI:
Using expansion instrument combined with metallographic analysis and hardness measurement
a continuous cooling transformation (CCT) curves of new Nb-V microalloyed bainite rail steel 20 mm plate (/% :0. 24C
0. 39Si
1. 86Mn
0. 007S
0. 002P
1 • 36Cr
0. 33Mo
0. 04Nb
0. 11V) are determined
the effect of cooling rate 0. 04 〜4. 0 °C/a on microstructure and hardness of steel are studied. The results show that the Bs point of tests steel is lower than 400 °C
when the cooling rate is in the range of 0. 1 to 0. 8 Y/s
the whole bainite structure can be obtained
which is consistent with the bainite rail alloy design principle ; the rolled microstructure of test steel is lath bainite and a small amount of martensite. The strength
plasticity
toughness and hardness of the rolled state are well matched
which meets the relevant technical conditions of the current bainitic rail production.