Effect of Carbon Addition on Magnetic Order in Mn-Al-C Alloys

Muriel Tyrman (1) , Alexandre Pasko (1) , Loic Perriere (2) , Victor H. Etgens (3) , Olivier Isnard (4) , Frédéric Mazaleyrat (1)

1 SATIE-MME - Matériaux Magnétiques pour l'Energie
2 ICMPE - Institut de Chimie et des Matériaux Paris-Est
3 UVSQ - Université de Versailles Saint-Quentin-en-Yvelines
4 NEEL - MRS - Matériaux, Rayonnements, Structure

Obtaining 100% of metastable τ-phase (L10) in Mn-Al alloys needs addition of carbon and Mn in excess to stabilize the phase. The excess of Mn could lead to partial antiferromagnetic coupling, that would result in a reduction in magnetization, which is in agreement with the experimental results. To clarify this question, (Mn0.55Al0.45)100−xCx alloys, with x between 0 and 2, were rapidly quenched from the melt (by melt-spinning) and annealed at 550 • C. In the as-cast state, the sample is in the hexagonal paramagnetic ε-phase, and after annealing, the sample is in the tetragonal ferromagnetic τ-phase. Different routes for the addition of carbon were used. The structural properties were determined by neutron diffraction, and the magnetic properties by means of VSM measurements and neutron diffraction (ND).

Mots clés: Neutron diffraction; Magnetic coupling; Magnetic moment; Weiss plot; Structural properties

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Muriel Tyrman, Alexandre Pasko, Loic Perriere, Victor H. Etgens, Olivier Isnard, et al.. Effect of Carbon Addition on Magnetic Order in Mn-Al-C Alloys. IEEE Transactions on Magnetics, 2017, 53 (11), pp.2101406 ⟨10.1109/TMAG.2017.2710639⟩. ⟨hal-01491135⟩