Microstructure Control for Spheroidization of Medium Carbon Steels with High Hole-expansion Property by Ultra Fast Cooling
In the present paper,the spheroidization of medium carbon steels was investigated by ultra fast cooling (UFC) after hot strip rolling.The result indicates that the microstructure consisting of spheroidized cementites in a fine ferrite matrix was realized after spheroidization annealing,and the initial microstructures after hot strip rolling have a great effect on the spheroidization behavior of cementites during annealing.In contrast to the conventional accelerated cooling,the ultra fast cooling technology,which restrains the diffusion of carbon atoms during hot rolling,is beneficial for the finely dispersed distribution of spheroidized cementites.With decreasing of fininshing temperature and stop-cooling temperature,the spheroidized cementites after annealing were more homogeneous and dispersed finely.Due to the long-time holding,it would be inclined to grow large for spheroidized cementites to form micro-voids during cold deformation,which could absorb the deformation energy and offer the plastic deformation space.Moreover,the homogeneous and dispersed finely microstructure avoids the combination of adjacent micro-voids and offers the excellent formability.The limit hole-expansion value of experimental steels could reach 165.8%.
Spheroidization Ultra fast cooling (UFC) Hole-expansion property Medium carbon steel
WANG Bin LIU Zhen-yu ZHOU Xiao-guang WANG Guo-dong
State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,Liaoning,China
国际会议
Asia Steel International conference 2012(第五届亚洲钢铁大会)
北京
英文
1-6
2012-09-23（万方平台首次上网日期，不代表论文的发表时间）