Effect of the Ga Content on the Magnetic Properties and Microstructure of the Nanocrystalline Ce-Fe-B Alloys

In this work, the Ce17Fe78-xB6Gax (x = 0 similar to 3) nanocrystalline alloys are prepared by the direct melt spinning method with the wheel speed of 18 m/s. The effect of Ga content on the hard magnetic properties and the crystal structure of Ce17Fe78-xB6Gax (x = 0 similar to 3) nanocrystalline alloys has been investigated. The results show that the Curie temperature (T-c) and the phase content hard magnetic Ce2Fe14B phase can be increased by adding appropriate amount of low melting point Ga element. The results of magnetic properties show that the enhanced magnetic properties are obtained for the alloy with x = 1: H-cj = 5.61 kOe, B-r = 5.4 kG, H-k/H-cj = 0.49, and (BH)(max) = 5.1 MGOe. The magnetization reversal characteristics of the alloys are analyzed by the recoil loops and the delta M-H curves; the sample with the Ga-doped shows a single hard magnetic behavior. The positive peak of delta M-H curve of the sample (x = 1) is obviously sharper and the peak value is higher, indicating the strongest magnetic interaction between grains. The reasons of the enhanced magnetic properties for the Ce-Fe-B alloy by the Ga addition are analyzed depending on the microstructure.