Değiş-Tokuş Etkileşimi Çiftlenimli Nanomıknatısların Manyetik Özelliklerinin İncelenmesi
Özet
In this work, high performance exchange-coupledmanganesebismuth manganeseboron (MnBi MnB) andironplatinum manganeseboron (FePt MnB) nanocomposite magnets wereproduced. Firstly, the functionality of the magnetically soft MnB phase was provedby density functional theory (DFT) calculations which predicts 1.915 μB magneticproperty per MnB unit that corresponds to 158 emu g at 0 K. MnxB100-x alloys werefabricated by arc melting technique. Structural analysis showed that startingmelting from Mn55B45 composition results single phase orthorombic MnB structure.Saturation magnetization, anisotropy constant and Curie temperature of MnB alloywere determined by magnetization measurements as 130 emu g, 517x103 erg gand 566 K, respectively. For exchange-coupling with a hard magnetic phase, bulkMnB alloy was milled for controlled durations. Results showed that 7 h of millingreduced the crystallite size to 11.6 nm and saturation magnetization to 85 emu g.
