High coercivity in Mn-Ga-Cu alloys

Abstract

Mn-Ga-Cu alloys were produced by melt-spinning and subsequent annealing. The coercivity of the Mn-Ga-Cu alloys was dependent on the Cu content and the annealing conditions. The coercivity of the Mn65Ga20Cu15 alloy annealed at 573 K for 10 h, iHc = 23.8 kOe, was comparable to that of rare-earth-based magnets. The hard magnetic phase of the Mn65Ga20Cu15 alloy was found to be fine D022-Mn3Ga grains, formed from the fcc phase during annealing.