Structural and Magnetic Properties of Fe Doped Mn-Ga Ribbons

Abstract

Abstract. In the present work we study the effect on structural and magnetic properties due to the introduction of Fe in Mn 2 Ga system. Mn 0.7-x Fe x Ga 0.3 (x = 0.1 to 0.3) alloys were prepared with Ar arc-melting as base materials which were subsequently converted to ribbons using melt-spinning technique with velocity ranged from 20 to 35 m/s. Some of the materials were heat treated in a temperature range from 550 to 850 °C and for different time span, from 10 minutes to 1 hour. Alloys were studied by various characterization techniques (EDX, X-ray diffraction, magnetization versus temperature and field). The magnetic properties are improved with the increase of Fe content, Ms rises almost an order of magnitude from 0.05 per formula unit to 0.5 μ B while low temperature coercivity reached 3.5 kOe. The temperature and duration of the thermal processing also plays a significant role. Two phases were detected, the one being stable above 973 K. The materials present two main Curie temperatures, one above 500 K and one transition below room temperature.