Enhanced Magnetoelastic Performance In Pr/Mn-Doped Laves Phase (Tb,Ho)Fe-2 Compounds

Magnetostrictive TbxHo0.Pr-8-x(0).Fe-2(1).Mn-8(0).(1)(0 <= x <= 0.20) alloys are prepared by arc-melting and subsequent annealing. The dopant of Pr/Mn introduced into RFe2 compounds effectively stabilizes the forming of single C15 Laves phase at ambient pressure. The easy magnetization direction (EMD) varies when Tb content increases, which is accompanied by a crystalstructural transition. EMD lies along < 100 > axis for x <= 0.05, rotating to < 111 > axis for x <= 0.12, with a tetragonal symmetry changing to a rhombohedral one. Magnetocrystalline-anisotropy compensation is obtained with the optimized composition of x = 0.12, shifting to the Tb-poor side in comparison to Pr/Mn-free counterpart. An enhanced effect on magnetoelastic properties is achieved in Tb0.12Ho0.Pr-68(0).Fe-2(1).Mn-8(0).(1), which simultaneously possesses a low anisotropy and high magnetostriction performance, i.e. lambda(S) similar to 420 ppm, lambda(111) similar to 970 ppm, and a large low-field lambda(a) similar to 390 ppm/2 kOe, being 30 % higher than that of Pr/Mn-free compound. Combining low-cost light rare earth Pr with the lower Tb content, Tb0.12Ho0.68Pr0.2Fe1.8Mn0.1 may make it promising solution in magnetostrictive applications.