Structure, thermal stability and magnetostrictive properties of PrFex (1.5 ≤ x ≤ 3.0) alloys

Polycrystalline alloys PrFex (x = 1.5, x = 1.8, x = 1.9, x = 2.0, x = 3.0) have been prepared by arc-melting and subsequent high-pressure synthesis method. Their structure, thermal stability, easy magnetization direction and magnetostriction are investigated. Almost single Laves phase (MgCu2-type) is found in sample with x = 1.9. Samples with x = 2.0, x = 3.0 consist of PrFe1.9 phase with MgCu2-type cubic structure and α-Fe phase. The Curie temperature (238 °C) and the decomposed temperature (408 °C) of PrFe1.9 alloys are derived from M–T curves. The easy magnetization direction of PrFe1.9 Laves phase lies along [1 1 1] axis at room temperature which is verified by Mössbauer spectrum. Furthermore, PrFe1.9 alloy shows a large magnetostriction λ|| – λ⊥ = 1081 × 10−6 at a magnetic field of 13 kOe.