本研究主要探討磁性/介電複合型吸收材料，將鎳鋅鐵氧粉體與石墨烯粉體摻於高分子基材Epoxy中，製作成複合電磁波吸收試片。探討其摻雜量、鎳鋅鐵氧體粉體粒徑、厚度對於反射損失之關係，並針對特定頻段設計出相對應之吸波材料之目的。
本研究在不同的鎳鋅鐵氧體粒徑分布和摻雜量下，可以發現Epoxy/鎳鋅鐵氧體試片介電損耗發生在高頻16GHz的位置，磁性損耗發生在低頻6GHz以下的位置，介電損耗和磁性損耗隨著摻雜量的增加而增加，試片的介電常數實部和導磁係數實部的數值和粒徑大小分部多寡的不同。細粒徑所造成的磁性損耗較低，但具有提高製作良率好處，反之顆粒越大則容易使試片在製作過程中失敗，但具有較高的損耗。反射損失估算結果得到，粒徑較大之粉體於低頻段有較好的吸收效果，當粉體為大粒徑且在高摻雜量的情況下，試片有機會能達到預期設定的中心頻率5GHz，反射損失-10dB且適當厚度的目標。
在不同石墨烯粉體摻雜重量下， Epoxy/鎳鋅鐵氧體/石墨烯複合試片介電及磁性損耗在低頻6GHz以下有微量的提升，但是效果不顯著。在反射損失估算結果可以得到，石墨烯在最高摻雜重量的情況下，有機會能達到預期設定的目標。若在低頻處要有更好的吸收效果仍以添加磁性材料為主。

This research presents the effects of the size distributions of Ni-Zn ferrite powders as well as addition of graphene on the absorbing properties of electromagnetic wave of epoxy/Ni-Zn ferrite/Graphene composite material. Ni0.5Zn0.5Fe2O4 powder was prepared by using conventional solid-state method, calcined at 1100℃for 2 hours. Three distinct size-distributions of Ni-Zn ferrite powers were isolated through contrived sieving-method and extra ball milling. The experimental measurements and theoretical analysis showed that there are two wave-absorbing mechanisms for the epoxy/Ni-Zn ferrite composite material, magnetic loss for low-frequency absorption of 2-6 GHz and dielectric loss for high-frequency absorption of 16-18 GHz. The absorbing efficiency of the composite materials increases with the size and volume fraction of Ni-Zn ferrite powers in the absorbing materials. For the object of reflection loss less than -10 dB centered at 5 GHz, 18.5 vol% of Ni0.5Zn0.5Fe2O4 with distribution of large power mixed with epoxy is recommended, for which the thickness of the composite material is expected less than 7 mm. For the study of effect of graphene on the absorbing properties, the present experiment demonstrated that reflection loss of -10 dB, centered at 5 GHz, and smaller thickness of composite material was possible for the addition of 3.25 vol% of graphene.

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