强磁场下奥氏体化温度对Fe-0.76%C钢先共析铁素体组织的影响  

Effect of austenizing temperature on the microstructure of proeutectoid ferrite in Fe-0.76%C alloy under high magnetic field

作　　者：宫明龙[1] 赵骧[1] 王守晶[1] 宋建宇[1] 左良[1] 

机构地区：[1]东北大学材料各向异性与织构教育部重点实验室,沈阳110004

出　　处：《材料与冶金学报》2008年第3期187-191,共5页Journal of Materials and Metallurgy

基　　金：国家自然科学基金资助项目(50771026);国家自然科学基金杰出青年基金资助项目(50325102)

摘　　要：借助于光学显微镜研究12T磁场对Fe-0.76%C合金在不同奥氏体化温度下保温30 min后以2℃/min冷却条件下先共析铁素体显微组织形貌变化.结果表明:在相同奥氏体化温度条件下,强磁场热处理样品中的先共析铁素体的面积分数和晶粒数量明显高于非磁场热处理样品中先共析铁素体的面积分数和晶粒数量.原因可归结为强磁场提高了先共析铁素体形核驱动力及强磁场使共析点向高碳高温方向移动.随着奥氏体化温度升高先共析铁素体晶粒沿着强磁场方向伸长的趋势明显越弱.奥氏体晶粒随着奥氏体化温度逐渐增大导致铁素体晶核之间的距离增大,从而造成奥氏体中的Fe原子向先共析铁素体晶粒扩散的距离增大的速度减慢所致.The present studies are to investigate the microstructure features of proeutectoid ferrite during transformation from austenite to ferrite at different austenizing temperatures without and with applying the magnetic field （12T） on Fe-0. 76% C alloy. It was found that the fraction and the number of proeutectoid ferrite grains with magnetic field heat treatment were more than those without magnetic field heat treatment. The possible reason is that the magnetic field increases the driving force of proeutectoid ferrite nuclei and shifts the eutectoid point to higher carbon and higher temperature sides. The proeuteetoid ferrite grains elongated along the magnetic field direction, and the angle between the major axis of proeutectoid ferrite and magnetic field direction was increased with the increase of austenizing temperature. The possible reason is that the coarse austenite grains could weaken the diffusion rates of Fe atom to proeutectoid ferrite grains.

关 键 词：强磁场 0.76%C铁碳合金 先共析铁索体 显微组织 

分 类 号：TG115.5[金属学及工艺—物理冶金]