本計畫研究以鋇錳銅鈦鐵氧體BaFe12-x(Mn0.5Cu0.5Ti)x/2O19為電磁吸收材料主要成分，並與Epoxy混合製成複合吸波試片，在背置金屬板的條件下，以數值分析方式探討如何降低其反射損失的方法。本研究實驗中以鋇錳銅鈦鐵氧體中錳、銅及鈦莫耳比例x、粉體製備的煆燒溫度為實驗變數，並在頻率範圍2~18GHz內量測該複合吸波試片的複導磁係數與複介電常數。以12GHz為中心頻率的條件下，探討在何種製作參數下可以得到最佳的反射損失及較薄的試片厚度，另外探討摻雜CNF後的樣本與未摻雜樣本在吸波能力及應用條件上的差異。本實驗結果中，在煆燒溫度1250℃且微量取代比例x=1的條件下，以粉體50wt%之比例所製備的BaFe11(Mn0.5Cu0.5Ti)1/2O19(x=1)/Epoxy試片在12GHz時有較高的磁損耗能力，但介電損耗能力仍不明顯，經數值分析後於12GHz時的匹配厚度為7.3mm時，反射損失數值為-18.47dB，-10dB頻寬為2.1533GHz，與當初設立之目標比較，僅達成-10dB頻寬大於2GHz的標準。為改善介電損耗能力較低的情況，將添加CNF進行摻雜。
本研究分別以0.5wt%及1wt%之CNF對50wt%的BaFe11(Mn0.5Cu0.5Ti)1/2O19(x=1)粉體進行摻雜，並與Epoxy製成BaFe11(Mn0.5Cu0.5Ti)1/2O19/CNF/Epoxy試片，結果顯示於12GHz的介電損耗正切數值將與CNF摻雜量成正比，於1wt%摻雜量時有最高介電損耗正切0.22，但磁損耗正切卻與CNF摻雜量成反比，推測原因可能是因為CNF含量的增加，導致複合材料內部的磁通量不連續，進而使磁損耗正切數值下降。
在12GHz時，當CNF摻雜量為0.5wt%且試片厚度為5.85mm時，反射損失達-42.42dB，-10dB頻寬為1.51GHz，-20dB頻寬為0.61GHz，當CNF摻雜量提升至1wt%時，試片厚度將減少至1.95mm，卻也犧牲反射損失及頻寬數值，僅達-11.3dB，而-10dB頻寬為1.49GHz，由此可發現摻雜少量的CNF將有較佳反射損失數值，若再提升CNF摻雜量雖無法提升反射損失數值，但可使試片厚度更加輕薄。總結以上可得知當CNF摻雜比例為0.5wt%時的反射損失數值較好，其-10dB頻寬甚至優於1wt% CNF摻雜量之表現。

This study systematically analyzed the effect of sintering temperature and mole ratio x(x=1,2,3) on the reflection loss for BaFe12-x(Mn0.5Cu0.5Ti)x/2O19/CNF/Epoxy as a wave absorber centered at 12GHz (Ku band) to reduce interference of electromagnetic waves. The barium ferrite powders were prepared by using solid phase synthesis method. Complex permeability and permittivity were deduced from measured S-parameter and reflection loss was calculated accordingly for the composite material with assumed thickness and backed on a metal plate. The largest magnetic loss tangent of barium ferrite occurred with x = 1 and sintering temperature of 1250℃. The theoretical computation suggested that the lowest reflection loss at 12 GHz was -42.42 dB for a composite material with a thickness of 5.85 mm and consisting of 50wt% of barium ferrite and 0.5wt% of CNF.

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