Design of high resistivity light-rare-earth-based PrFe1.93 magnetostrictive alloys: Si doping and high-pressure annealing

Abstract

Light-rare-earth-based Pr(Fe1-xSix)1.93 alloys (0⩽x⩽0.1) with pure cubic Laves phase were synthesized by high-pressure annealing method. Si substitution effects on magnetic, electrical and magnetostrictive properties of light-rare-earth-based Pr(Fe1-xSix)1.93 alloys were systematically investigated. It was found that the lattice parameter a and Curie temperature TC of the cubic Laves phase in the alloys increase with the increasing Si content up to x=0.05, which might be ascribed to the preferential occupation of Si in the Laves phase interstitial sites. The magnetization at the maximum available field of 15 kOe, σ15k, decreases monotonically with the increasing x. A significant increase of 67% in electrical resistivity was observed in Pr(Fe0.9Si0.1)1.93 alloy at room temperature. The magnetostriction at the field of 3 kOe of Pr(Fe0.95Si0.05)1.93 is about 542 ppm, which is even larger than the saturation magnetostriction of heavy-rare-earth-based Tb0.2Dy0.22Ho0.58Fe2 single crystal (λs = 530 ppm). The attractive price, lower eddy current loss, together with high magnetostrictive response suggest that the Pr(Fe0.95Si0.05)1.93 alloy might be a good candidate material for the potential magnetostrictive applications.