Influence of Al and Ga on Formation of the La(Fe,Si)₁₃-Type Phase in the LaFe_11.14Co_0.66Si_1.2-xM_x(where x=0.1, 0.2, 0.3; M=Al, Ga) Alloys

Abstract

In the present work the influence of Al and Ga on formation of La(Fe,Si)13-type phase in magnetocaloric LaFe11.14Co0.66Si1.2−xMx (where x = 0.1, 0.2, 0.3; M = Al, Ga) alloys subjected to annealing at 1323 K for 15 days was studied using the Mössbauer spectroscopy. For annealed samples, two crystalline phases were recognized: the dominant paramagnetic La(Fe,Si)13-type phase, and minor fraction of ferromagnetic α-Fe(Co,Si). It was revealed that Al improved formation of 1:13 phase in contrast to Ga, which caused reduction of the ability of formation of the expected phase.