PEMBUATAN MAGNET BERBASIS BaFe12O19 - SiO2 DAN KARAKTERISASINYA
ABSTRAK
Pembuatan dan karakterisasi magnet telah berhasil dilakukan dengan mencampurkan serbuk bahan magnet BaFe12O19 dan serbuk SiO2. Variasi komposisi BaFe12O19 : SiO2 terdiri dari 100:0, 80:20, 70:30, 60:40 dan 50:50 dalam % berat. Pencampuran dilakukan dengan metode dry milling menggunakan Planetary Ballmill (PBM) selama 48 jam. Serbuk hasil pencampuran dicetak secara anisotropi pada tekanan 35 kgf/cm2sehingga menghasilkan pelet dengan diameter 12 mm dan tebal 3-5 mm. Pelet tersebut kemudian dibakar (sinter) pada suhu 600 °C, 650 °C, 700 °C, 750 °C, 800 °C dan ditahan pada masing-masing suhu tersebut selama 2 jam sehingga diperoleh sampel uji. Karakterisasi sampel uji meliputi analisa sifat fisis, struktur mikro dan pengukuran sifat magnet (histerisis). Hasil identifikasi pola XRD menunjukkan bahwa fasa yang terbentuk terdiri dari BaFe12O19, SiO2 dan Fe3O4. Morfologi permukaan yang diamati
dengan SEM menunjukkan bahwa ukuran butir < 1 μm. Berdasarkan hasil pengukuran dengan permagraph, diketahui bahwa sifat magnetik yang terbaik diperoleh pada komposisi 80:20 dengan suhu sintering 800 oC di mana nilai koersifitas (Hc), remanensi (Br)dan energi produk maksimum (BHmaks)
berturut-turut 1,656 kOe, 0,81 kG dan 0,414 MGOe.
MANUFACTURE OF BaFe12O19 - SiO2BASED MAGNETAND CHARACTERIZATION
ABSTRACT
Preparation and characterization of magnetic have been successfully carried out by mixing the magnetic material BaFe12O19 powder and SiO2 powder. The Ba
Fe12O19/SiO2 ratios used were 100:0, 80:20, 70:30, 60:40 and 50:50 by weight
percent. Mixing is done with a dry milling method using Planetary Ballmill (PBM) for 48 hours. Powder blending results was printed on anisotropy pressure 35 kgf/cm2 to produce pellets with a diameter with of 20 mm and 5 mm thickness.of 12 mm and 3-5 mm thickness. The pellets are then burned (sintered) at a temperature of 600 °C, 650 °C, 700 °C, 750 °C, 800 °C and held at each of these temperatures for 2 hours in order to obtain test samples. Characterization of the test sample includes the analysis of physical properties, microstructure and measurement of the magnetic properties (hysteresis). The XRD pattern identification results showed that the phase is formed consisting of BaFe12O19,
SiO2 and Fe3O4. The surface morphology were measured by SEM showed that the
grain size ˂ 1 μm. Based on the results of measurements with permagraph, it is known that the best magnetic properties are obtained on the composition of 80:20 with sintering temperature of 800 °C where the coercivity value (Hc), remanence
(Br) and maximum energy product (BHmaks) respectively 1.656 kOe, 0.81 kG and
0.414 MGOe.
