Solidification Characteristic and Microstructure Evolution of Fe-Mn-C TWIP Steel
The solidification temperatures of Fe-22Mn-0.7C and Fe-22Mn-0.4C TWIP steel measured by continuous cooling method are 1270℃ and 1380℃,1314℃ and 1405℃,with the solidification ranging 110℃ and 91℃ respectively.The solidification ranges of TWIP steels calculated byThermoCalc and JmatPro are a little widerbut still acceptable.The thermal conductivity of TWIP steel is lower than those of carbon steel and stainless steel,which could be revealed as a linear function of temperature k(T)=0.010214T (℃)+14.721101in the range of 0~1200℃.It is also found that both Mn and C weaken the thermal conducting property of austenite phase.According to the regressed relationship between the thermal conductivity and the solute concentration,Mnpresents a decreasing effect about one fifth of C.In addition,the segregation behavior of C and Mn is quite evident in microscope with the segregation ratio ranging from 0.8~1.5,which is induced by the weakening of the back diffusion and the descending of equilibrium partition coefficients.It is observed that the columnar grains are more developed in the steels with higher Mn and C,in which the CET is also much later.It is more apt to satisfy the constitutional undercooling conditions for TWIP steel than for low carbon steel,which should be the explanation for the promotion of the dendrite growth at the interface under the present thermal condition.
TWIP steel thermal conductivity microsegregation dendrite solidification
LAN Peng LU Mingang ZHANG Jiaquan
School of Metallurgical and Ecological Engineering, University of Science & Technology Beijing,Beiji School of Metallurgical and Ecological Engineering, University of Science & Technology Beijing,Beiji
国际会议
成都
英文
255-259
2016-11-16（万方平台首次上网日期，不代表论文的发表时间）