Anomalies in magnetoelastic properties of NdFe10V2 alloy

Magnetostriction and thermal expansion of NdFe10V2 alloy are reported. Experimental isotherms of the magnetostriction show a hill type maximum below 1 T which is more pronounced around 130 K, corresponding to that of spin-reorientation transition in this alloy. The hills are accompanied by a large zero-field magnetostrictivity. Hence, observed maxima are attributed to the minimum of magnetocrystalline anisotropy, which is expected at spin-reorientation temperature. Isotherms of magnetostriction above 50 K saturate at fields of 4 T and above. Studying of the temperature dependence of saturation magnetostriction shows that the experimental results are in good agreement with the prediction of a theory composed by a combination of Callen's single particle model and mean-field approximation of two particle magnetoelastic interactions. Thermal expansion measurements show that the thermal expansion coefficient is negligible at temperatures below 50 K, then increases with temperature linearly until 230 K, and finally remains constant, around 5×10–6 K–1, near room temperature. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)