Evolution of magnetic and transport properties in (Cr1−xMnx)2AlC MAX-phase synthesized by arc melting technique

Abstract

Abstract Herein we initiate a comeback to the arc melting technique to produce MAX-phase solid solutions. Bulk samples of (Cr1−xMnx)2AlC MAX-phase with X = 0, 0.025, 0.05 and 0.1 were synthesized and studied by means of X-ray diffractometry, scanning electron microscopy in combination with energy-dispersive X-ray spectroscopy. Samples were established to be homogeneous with an incorporation of Cr7C3, AlCr2 and Al2O3 secondary phases which is slightly increasing with the raise of the dopant concentration. Manganese successfully intermixes in the MAX-phase structure due to the effect of the high-energetic plasma during the melting process. SQUID magnetometry identified the co-existence of ferro- and antiferromagnetic interactions with the latter prevailing in high temperatures and being attributed to the MAX-phase. Magnetic state transitions were observed at approximately 4 K and 5 K for doped samples which was associated with the presence of the marginal amount of ferromagnetic Mn-based secondary phases. The negative component of magnetoresistance was observed in highly doped samples at low temperatures that is likely due to the influence of ferromagnetic secondary phases as well. Transport properties measurement revealed the satisfactory quality of the produced samples.