Formation and Soft Magnetic Properties in Fe-Si-B Amorphous Alloy by Adding Dysprosium

• Main Authors: Ting-Yi Chen, 陳庭溢
• Other Authors: 陳適範
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/f67n3f

碩士 === 國立臺北科技大學 === 材料科學與工程研究所 === 96 === In this investigation, we explored the effects of a small dysprosium(Dy) addition in the glass forming ability and remained the soft magnetic properties of Fe-Si-B amorphous alloy. Multi-component alloy ribbons with compositions of (Fe0.75Si0.10B0.15) 100-XDyX(X=0,0.5,1 and 2at.%) were synthesized by the single roller melt-spinning method. To examine the glass transition temperature(Tg), crystallization temperature(Tx) and Curie temperature(Tc), the as-cast ribbons was measured with a differential scanning calorimetry(DSC) at a heating rate of 0.33 K/s. Microstructure were examined by X-ray diffractometer(XRD) and scanning electron microscopy(SEM). The saturation magnetization(Ms) and coercive force(Hc) were examined by a vibrating sample magnetometer(VSM) in an applied magnetic field 5000 Oe. To examine the Curie temperature(Tc) and magnetic phase with a thermal gravimetric analyzer(TMA) at a heating rate of 0.33 K/s and in an applied magnetic field 110 Oe. Tg appears in samples with X≧1 at.%, and Tg and Tx increase from 780 to 804K and 833 to 887K, respectively, with increasing Dy content from 0 to 2at.%. The maximum ΔTx(=Tx-Tg) value of 83K for the 2at.% Dy alloy. The Dy-contenting metallic glassy alloy incurred the Tc was decreased from 714 to 625K, the Ms was decreased from 1.58 to 1.50T and the Hc was decreased from 27.77 to 22.28A/m. In condition, minor addition of Dy causes the appearance of the glass transition and a supercooled liquid region before crystallization. The small addition of Dy was very effective in improving glass-forming ability and remained the soft magnetic properties of Fe-Si-B alloys.