Magnetic properties and magnetostriction of Pr_xNd_1-xFe_1.9 (0≤x≤1.0) alloys at low temperature

The crystal structure, magnetic and magnetostrictive properties of high-pressure synthesized Pr_xNd_1-xFe_1.9 (0≤x≤1.0) alloys were studied. The alloys exhibit single cubic Laves phase with MgCu₂-type structure. The initial magnetization curve reveals that Pr_0.2Nd_0.8Fe_1.9 has a minimum magnetocrystalline anisotropy at 5 K. The magnetostriction curve at 5 K shows that Pr_0.2Nd_0.8Fe_1.9 has a very good low-field magnetostrictive property, and the magnetostriction of the Pr_xNd_1-xFe_1.9 alloy in high magnetic field is attributable mainly to Pr. The temperature dependence of the magnetostriction (λ_||) at the field of 5 kOe shows that the substitution of Nd reduces the K₁ remarkably, and the values of λ_|| of Pr_0.2Nd_0.8Fe_1.9 and Pr_0.8Nd_0.2Fe_1.9 alloys are nearly five times larger than that of PrFe_1.9 alloy below 50 K; the λ_|| of Pr_0.8Nd_0.2Fe_1.9 reaches up to 1082 ppm at 100 K, which makes it a potential candidate for application in this temperature range.