Effect of Finishing Rolling Temperature on Microstructure and Mechanical Properties of Microalloyed TRIP Steels  

作　　者：MI Zhen-li JIANG Hai-tao LI Zhi-chao CHEN Mei-fang WANG Zhi-gang 

机构地区：[1]National Engineering Research Center for Advanced Rolling Technology,University of Science and Technology Beijing

出　　处：《Journal of Iron and Steel Research International》2013年第10期75-80,共6页

基　　金：Foundation Item:Item Sponsored by National Natural Science Foundation of China(50804005);Central Collegiate Basic Scientific Research Bursary of China(FRF-TP-11-005B)

摘　　要：Different samples of TRIP （transformation induced plasticity） steel obtained by two different hot rolling schedules are investigated by using a SEM （scanning electron microscope）. The microstructure is characterized by using an OM （optical microscope） for phase distribution and by EBSD （electron backscatter diffraction） for texture and phase mapping. ODF （orientation distribution function） graphs are used to investigate the effect of recrystallization behavior of the hot-deformed austenite on phase transformation during the controlled cooling process. The mechanical behavior is interpreted in terms of the strength of both hard and soft phases, in combination with the quantity, loca- tion and transformation kinetics of the mechanically induced martensite （TRIP effect）. The results show that more austenite grains exist in the steels obtained at finishing rolling temperature （FRT） of 750 ℃, which inherited the de- formation structure after the hot-rolling process. The instantaneous n value （ni） of those steels is kept high during a large range of strain before failure, while the tensile strength and total elongation of the steels with respect to the dif- ferent finishing rolling temperatures do not show any significant differences.Different samples of TRIP （transformation induced plasticity） steel obtained by two different hot rolling schedules are investigated by using a SEM （scanning electron microscope）. The microstructure is characterized by using an OM （optical microscope） for phase distribution and by EBSD （electron backscatter diffraction） for texture and phase mapping. ODF （orientation distribution function） graphs are used to investigate the effect of recrystallization behavior of the hot-deformed austenite on phase transformation during the controlled cooling process. The mechanical behavior is interpreted in terms of the strength of both hard and soft phases, in combination with the quantity, loca- tion and transformation kinetics of the mechanically induced martensite （TRIP effect）. The results show that more austenite grains exist in the steels obtained at finishing rolling temperature （FRT） of 750 ℃, which inherited the de- formation structure after the hot-rolling process. The instantaneous n value （ni） of those steels is kept high during a large range of strain before failure, while the tensile strength and total elongation of the steels with respect to the dif- ferent finishing rolling temperatures do not show any significant differences.

关 键 词：TRIP hot rolling） multiphase mierostructure） mechanical behavior EBSD 

分 类 号：TG335.11[金属学及工艺—金属压力加工]