Structure, Magnetic Properties, and Coercivity Mechanism of Rapidly Quenched Mn_{<italic>x</italic>}Ga Ribbons

Abstract

The microstructure, magnetic properties and coercivity mechanism of rapidly quenched rare-earth-free L1 0 -Mn 1.86 Ga and D0 22 -Mn 3 Ga permanent magnetic ribbons have been investigated. The high remanence M r of 61.3 emu/g and maximum energy product of 2.1 MGOe are obtained in L1 0 -Mn 1.86 Ga ribbons. The coercivity H C of L1 0 -Mn 1.86 Ga and D0 22 -Mn 3 Ga are 2.7 and 6.9 kOe, respectively. The different coercivity mechanism and exchange coupling behaviour have been discussed, upon the measurement of minor loops and Henkel plots. The minor second phase at grain boundaries in L1 0 -Mn 1.86 Ga ribbons may act as pinning center of domain wall, thus reduce the exchange coupling. Both ribbons with Curie temperature above 700 K may be promising permanent magnets at room temperature.

Effect of substrate temperature on structure, magnetic and electrical transport properties of Mn1.60Ga films

“…and 2.55 MGOe, respectively. The latter is larger than the maximum magnetic energy product of 2.1 MGOe for the reported L1 0 -Mn 1.86 Ga strip samples [17]. L1 0 -Mn 1.60 Ga thin film with large magnetic energy product is an excellent candidate for new rare earth-free and noble metal-free economic permanent magnets.…”