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PENGARUH KOMPOSISI POLYVINYL BUTYRAL (PVB) PADA PEMBUATAN BONDED MAGNET NdFeB TERHADAP
MIKROSTRUKTUR, SIFAT FISIS DAN MAGNET
ABSTRAK
Pembuatan bonded magnet merupakan magnet komposit yang dibuat dari serbuk magnet yang dicampur dengan perekat (binder) yang bersifat non-magnet. Proses pembuatan bonded magnet NdFeB dilakukan dengan mencampurkan serbuk magnet neodymium iron boron (NdFeB) komersil type MQP-B dengan serbuk polyvinyl butyral menggunakan beaker gelas. Perbandingan variasi komposisi serbuk magnet NdFeB dengan binder PVB sebesar (% berat) 98:2, 96:4, 94:6 dan 93:7 dari massa total sampel 8 gram. Setelah pencampuran serbuk, kemudian dicetak dengan menggunakan metode compression moulding dengan tekanan 8 ton selama 20 menit pada suhu pengerasan (curing temperature) 160 0C. Sampel yang telah dicetak dilakukan karakterisasi sifat fisis yang meliputi pengukuran densitas, analisis mikrostruktur menggunakan SEM-EDX dan karakterisasi sifat magnet yang meliputi pengukuran kuat medan magnet menggunakan Gaussmeter dan kurva histeresis menggunakan VSM. Hasil penelitian menunjukkan bahwa penambahan binder PVB pada bonded magnet NdFeB mengakibatkan penurunan densitas dan kuat medan magnet. Perolehan hasil densitas dan kuat medan magnet terbaik pada pembuatan bonded magnet, diperoleh dengan penambahan binder 2 % sebesar 5,66 g/cm3 dan kuat medan magnet sebesar 1862,4 G. Nilai Mr = 72,86 emu/gram, Ms = 103 emu/g, Hc = 8,490 KOe dan BHmax = 5,1 MGOe diperoleh pada penambahan PVB 2 %.
Kata kunci : Magnet bonded NdFeB, binder polyvinyl butyral, sifat fisis dan sifat magnet.
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INFLUENCE OF POLYVINYL BUTYRAL (PVB) COMPOSITION IN MANUFACTURING OF BONDED MAGNET NdFeB ON
MICROSTRUCTUR, PHYSICAL PROPERTIES AND MAGNETIC
ABSTRACT
Manufacture of bonded magnet is composite magnet material made by mixing magnetic powder with non-magnetic binder. The process in manufacturing bonded magnet NdFeB made by mixing powder of neodymium iron boron (NdFeB) commercial type MQP-B with a polyvinyl butyral powder using a glass beaker. The comparisons of variation in composing NdFeB magnets powders with a binder of PVB (% weight) are 98:2, 96:4, 94:6 and 93:7 0f 8 grams from total mass of the sample. After mixing the powder, it is molded by using a compression molding method with 8 tons pressure for 20 minutes at curing temperature 160 0C. The molded samples are conducted by characterizing the physical properties which include measurement of density, microstructure analysis using SEM-EDX and magnetic properties which include measurement of the magnetic field strength using a gaussmeter and hysteresis curve using VSM. The result of the study shows that the addition of and binder PVB in bonded magnet NdFeB causes a decrease in the density and magnetic field strength. The best result of density and magnetic field in the manufacture of bonded magnets is obtained by the addition of 2 % binder of 5.66 g/cm3 and strong magnetic field of 1862.4 G. the score of Mr = 72.86 emu/g, Ms = 103 emu/gram, Hc = 8.490 KOe and BHmax = 5.1 MGOe was obtained on the addition of PVB 2 %.
Keywords : Bonded Magnets NdFeB, polyvinyl butyral binder, physical properties and magnetic.
