Caiyin YOU
金属学报(英文版)
Magnetic properties, phase evolution and microstructures of Pr9.44Fe90.56-xBx (x=7.16 and 4.76) nanocomposite magnets have been investigated. Both as-spun ribbons exhibit two-step demagnetization curves, indicating the feature of partial crystallization. By using differential scanning calorimeter (DSC) measurements, remained amorphous phase of ribbon with x=7.16 shows a higher crystallization temperature. At optimum annealing temperature of 650 ℃ for 10 min, better magnetic properties, Mr=1.01 T, jHc=796 kA/m and (BH)max=136 kJ/m3 were obtained in the sample with x=4.76. Transmission electron microscopy (TEM) observation confirms that the sample with x=4.76 possesses much finer grain size, which causing a better exchange coupling between soft and hard magnetic grains.
关键词:
Nanocomposite magnet
,
melt spinning
,
exchange coupling
,
microstructure
马殿国
,
王英敏
,
李艳辉
,
张伟
金属学报
doi:10.11900/0412.1961.2016.00485
研究了Co含量对熔体快淬Fe55-xCoxPt15B30 (x=0~45,原子分数,%)合金热处理前后的组织结构和磁性能的影响。结果表明,添加Co可提高Fe55-xCoxPt15B30合金的非晶形成能力,使x=15~45的快淬合金形成非晶态。经适当热处理后,合金中形成了由有序面心四方结构的永磁(Fe, Co)-Pt (L10)相和软磁(Fe, Co)2B相及(Fe, Co)B相组成的纳米复相组织,显示出永磁性;添加Co的合金组织得到明显细化,x=15~45合金平均晶粒尺寸均约为18 nm;其中x=15合金具有最佳的永磁性能,磁能积达到94.4 kJ/m3。合金的矫顽力随Co含量的增加而增大,在x=30时达到最大值413.7 kA/m后,随Co含量的进一步增加而减小;这是由于不同Co含量使L10相的c/a值发生变化而导致其磁晶各向异性变化的结果。
关键词:
非晶态合金
,
纳米复相永磁材料
,
L10-FePt相
,
结晶化
,
磁性能
