Magnetic ordering and coercivity of {Y, Tb}Ni4Si, NdNi3TSi (T = Mn - Cu) and Sm1-xTbxNi3FeSi solid solutions

Magnetic ordering of the polycrystalline YNi4Si-type YNi4Si, disordered YNi4Si-type TbNi4Si and NdNi3CoSi (space group Cmmm, N 65, oC12), and CaCu5-type NdNi3TSi (T = Mn, Fe, Cu) and Sm1-xTbxNi3FeSi (x = 0.25 and 0.5) solid solutions (space group P6/mmm, N 191, hP6) have been studied by magnetization measurements. Down to 2 K, YNi4Si is paramagnetic, whereas TbNi4Si, NdNi3MnSi, NdNi3FeSi, NdNi3CoSi and NdNi3CuSi show ferromagnetic ordering (TC) at 30 K, 71 K, 120 K, 20 K and 5.6 K and field sensitive transitions (Tm) at 10 K, 43 K, 63 K, 16 K and 3.8 K, respectively. Sm.75Tb.25Ni3FeSi and Sm.5Tb.5Ni3FeSi show ferromagnetic-antiferromagnetic transformations below ferromagnetic ordering at 166 K and 120 K, respectively.