奈米晶NdFeTiCB系薄帶磁性及矯頑機制之研究

• Main Authors: LiLan Kuo, 郭俐蘭
• Other Authors: 張文成
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/46677473812417898970

碩士 === 國立中正大學 === 物理系 === 90 === Abstract This research is to adopt Co and minor Ti/C co-substitution in rare earth lean and boron enriched NdFeB-type nanocomposite alloy ribbons for enhancing the remanence and magnetic energy product while keeping a proper coercivity. High performance exchange coupled NdFeB-type nanocomposite with easy magnetization are thus explored. 1. For Nd10FebalTiCBx (x=8~10), the intrinsic coercivity and the volume fraction of hard magnetic phase (2:14:1) decrease with the decrease of B content (x). The highest the remanence and magnetic energy product are found in the alloy ribbons with x=9. When x is lower than 9, the volume fraction of soft magnetic phase (Fe3B) appears and decreases with the decrease of B content (x). 2. For Nd10Febal.CoxTiCB9 (x=0, 2.5, 5, 7.5, 10), the increase of Co substitution, the alloy ribbons increase the remanence and magnetic energy product. Co-addition leads to the increment of the Curie temperature of the magnetic phase and improves the thermal stability of the ribbons 3. For Nd10Febal.TiCxB10-x(x=1,1.5, 2, 2.5, 3), minor carbon substitution with boron in the alloy ribbons leads to the enhancement of coercivity, remanence, and magnetic energy product below x=2. The highest coercivity and volume fraction of hard magnetic phase (2:14:1) are found in the alloy with x=2. On the other hand ,the highest remanence and magnetic energy product was found in the alloy ribbons at x=2.5. 4. For Nd10Febal.TiC2B8 and Nd10Febal.Ti2C2B7, minor Ti substitution for B in the alloy ribbons leads to the enhancement of remanence and magnetic energy product, while the coercivity is slightly decreased. Ti was found effective not only in grain refining but also in suppressing the formation of Fe3B phase. 5. In summary, the optimum magnetic properties of Br=9.5kG, iHc=9.5kOe and (BH)max=17.5MGOe, α-loss=-0.11%/℃ and β-loss=-0.44%/℃ are obtained in Nd10Febal.Ti2C2B7.