The evolution of solidified structure of S50C steel during heat treatment in compact strip production process was studied through an ultra-high-temperature confocal scanning laser microscope.It was found that the soli...The evolution of solidified structure of S50C steel during heat treatment in compact strip production process was studied through an ultra-high-temperature confocal scanning laser microscope.It was found that the solidified structure consisted of dendritic crystals with secondary dendrite arm spacing ranging in 32-120μm,where carbon segregation was evident,and the dendrite arms wereα-Fe.The insignificant change was observed at a soaking temperature of 1180℃,whereas at 1300℃,the finer structure firstly disappeared,and then,the coarsening decreased,indicating that carbon tended to be homogenized.Therefore,the microsegregation was improved at 1300℃for 15 min.The phase transformation ofα-Fe→γ-Fe enhanced the carbon diffusion,and the evolution of the equivalent radius req was controlled by carbon diffusion.The diffusion coefficient of carbon(D=15μm2/s)was determined by using the inverse problem method.展开更多
基金The authors would like to thank the National Natural Science Foundation of China(No.62071034)the management of Jiuquan Iron and Steel(Group)Co.,Ltd.,China for the financial support and giving permission to publish this work.
文摘The evolution of solidified structure of S50C steel during heat treatment in compact strip production process was studied through an ultra-high-temperature confocal scanning laser microscope.It was found that the solidified structure consisted of dendritic crystals with secondary dendrite arm spacing ranging in 32-120μm,where carbon segregation was evident,and the dendrite arms wereα-Fe.The insignificant change was observed at a soaking temperature of 1180℃,whereas at 1300℃,the finer structure firstly disappeared,and then,the coarsening decreased,indicating that carbon tended to be homogenized.Therefore,the microsegregation was improved at 1300℃for 15 min.The phase transformation ofα-Fe→γ-Fe enhanced the carbon diffusion,and the evolution of the equivalent radius req was controlled by carbon diffusion.The diffusion coefficient of carbon(D=15μm2/s)was determined by using the inverse problem method.
