稀土Dy对FePt合金微结构和磁性能的影响

应用XRD,SEM,EDS和PPMS等方法对DyxFe60.5-xPt39.5(x=0,0.5,1.0,1.5)纳米复合材料进行微结构和磁性能研究.研究发现,在1 300℃该合金是无序的面心立方相(FCC),而在600℃是以有序的面心四方相(FCT)的形式存在;当稀土Dy的添加量x为1.5时,FePt合金中出现富稀土相颗粒,并均匀弥散分布在基体FePt合金中,验证FePt合金对稀土Dy的固溶度在1.5%at.以内.随稀土Dy含量的增加FePt合金晶粒显著得到细化,当Dy添加量x为0.5,退火时间为5 h,该合金的矫顽力和剩磁比达到最大值μoHc=0.326 T,mr(Mr/Ms)=0.68,并得到最大的磁能积BH(max)=9.4 MGOe.认为稀土Dy的加入改善和提高了FePt合金的诸多性能.

Influence of Rare Earth Dy on the Microstructures and Magnetic Properties of FePt Bulk Alloy

The microstructures and magnetic properties of nanocomposite DyxFe60.5-xPt39.5(x=0,0.5,1.0,1.5) have been investigated by XRD,SEM,EDS and PPMS.It is found that the alloy exists on FCC at 1 300 ℃ and FCT at 600 ℃;and grains rich in rare earth appears in the FePt alloy when Dy content is 1.5%at.,so it confirms that the maximum solid solubility of Dy in Fe60.5-xPt39.5Dyx alloy is below 1.5%at.The grain size of the alloys is decreased with the Dy addition.The magnetic properties of the Fe60.5-xPt39.5Dyx(x=0,0.5,1.0,1.5) alloys reaches the maximum(μoHc=0.326T,mr(Mr/Ms)=0.68,BH(max)=9.4MGOe) when the Dy content is 0.5%at.and annealing time is 5 h.The conclusion is that Dy doping improves and enhances much properties of FePt bulk alloy.