- 學位論文
Fe-Si-B-Cu-Nb薄帶製粉及SWAP法製Fe-Si-B-Cr-C粉末成型之研究
Powders prepared from Fe-Si-B-Cu-Nb ribbons and forming by SWAP Fe-Si-B-Cr-C powders
摘要
本研究分為二個部分第一部分是Fe73.5Si13.5B9Cu1Nb3薄帶性質與製粉之研究，第二部分是使用SWAP法製造的Fe72.8Si11.2B10.8Cr2.3C2.9粉末成型固化。利用行星式球磨機製造出粉末，透過SEM (Scanning Electron Microscopy) 觀察粉末的型貌，並搭配粒徑分布儀測試其平均粒徑大小。利用XRD (X-Ray Diffraction) 與VSM (Vibrating Sample Magnetometer) 可以觀察薄帶在不同溫度下的性質變化。使用油壓機在12.6 MPa下將粉末成形，透過LCR量測儀測試其導磁率與品質因子變化、磁滯曲線儀測試飽和磁化強度與矯頑磁力。實驗顯示原始薄帶與SWAP粉末透過XRD分析顯示為寬廣繞射峰，呈現奈米晶或非晶結構，薄帶經過DTA (Differential Thermal Analyzer) 分析可觀察到居禮溫度為400°C與兩個結晶溫度分別為500°C、550°C，經過退火隨著Fe2B相之析出其內應變有增加之趨勢，且矯頑磁力明顯上升，在450°C時有最高飽和磁化強度介於1.8×104 至 1.9×104 G。薄帶經過球磨後其平均顆粒尺寸可達直徑數10 μm，粉末由不規則狀趨近於球狀，SWAP粉末則呈現平滑的球狀，且球磨的過程有結晶化的趨勢。而在SWAP粉末成型部分，披覆1 wt.%矽酸鈉與高溫環氧樹酯(H-epoxy)在300°C下固化的磁芯在測試頻率100 kHz~2000 kHz有最高的的品質因子為84、初始導磁率為17.4；披覆2 wt.%矽酸鈉與高溫環氧樹酯在300°C下固化有最佳飽和磁化強度介於 7×102 至 8×102 G；披覆1 wt.%矽酸鈉與PVB在150°C下固化有最低矯頑磁力0.21 Oe。
並列摘要
This research is composed of two parts. One part is the properties in Fe73.5Si13.5B9Cu1Nb3 ribbons and study the properties after milling. Another is the core properties compressed by SWAP Fe72.8Si11.2B10.8Cr2.3C2.9 powders. Utilizing ribbons to prepare the powders by planetary ball mill. The microstructure is observed by SEM. The mean size is obtained by the particle size distribution analyzer. The ribbon properties is observed by XRD and VSM at different annealing temperatures. The hydraulic press can compress the powders into cores at 12.6 MPa. The Q (quality factor) and μi (permeability) are examined by LCR Meter. Their Bm (saturation magnetization) and Hc (coercivity) are received by fluxgate magnetometer. For the ribbons, the DTA analysis shows that the curie temperature is at 400°C and two crystalline peaks are at 500°C and 550°C. The XRD analysis shows the second phase Fe2B begin to appear at 500°C and the maximum strain is 0.195 % in the ribbons at 600°C. The maximum Bm is between 1.8×104 to 1.9×104 G at 450 °C annealing. The powders can be reached to 10 μm but could be underwent crystallization during milling. For the cores, the maximum μi is 14 and Q is 84 between 100kHz - 2000kHz for 1 wt.% Na2SiO4 with H-epoxy at 300°C concreting. The minimum Hc is 0.21 Oe at 1 wt.% Na2SiO4 with PVB at 150 °C consolidation and the maximum Bm is between 7×102 to 8×102 G for 2 wt.% Na2SiO4 with H-epoxy at 300 °C consolidation.