液氮球磨Sm-Fe合金的组织演变

利用低温液氮球磨技术制备了Sm-Fe合金粉体，采用XRD、HRTEM和惰性气脉冲-红外-热导等方法对Sm2Fe17合金粉体在液氮球磨过程中的组织演变进行了研究。结果表明，液氮球磨可加速细化Sm-Fe合金粉体。球磨5 h后，Sm-Fe合金的晶粒尺寸约为10 nm，9 h后晶粒尺寸约为5 nm。Sm-Fe合金中的氮含量随着球磨时间的延长而增加，主轴转速150 r/min球磨9 h后，氮含量达1.62% (质量分数, 下同)。随着球磨时间的延长，Sm2Fe17相向非晶态转变，降低球磨转速可以延缓非晶的形成过程

Microstructure Evolution of Sm-Fe Alloy Prepared by Cryomilling in Liquid Nitrogen

The Sm-Fe alloy powders were prepared by cryomilling in liquid nitrogen. By means of XRD, HRTEM and Inert Gas Pulse-Infrared-Thermal Conductivity method, the microstructure evolution of the Sm2Fe17 alloy powders during the cryomilling process was studied. The results show that the grain sizes of Sm-Fe alloy powders were rapidly reduced by cryomilling in liquid nitrogen. The grain sizes of the alloy powders were about 10 nm and 5 nm after cryomilling for 5 h and 9 h, respectively. The nitrogen content in the Sm-Fe alloy powders increased with longer cryomilling time. After cryomilling at 150 r/min for 9 h, the content of nitrogen reached 1.62wt%. With increasing of the cryomilling time, the Sm2Fel7 phase changed to amorphous phase. Low cryomilling speed can slow down the formation of amorphous phases