Synthesis and Magnetostrictive Properties of High-Pr Content  ${\rm Sm}_{1-x}{\rm Pr}_{x}{\rm Fe}_{1.9}$ Cubic Laves Alloys
Polycrystalline Sm<sub>1-</sub><i>x</i>Pr<i>x</i>Fe<sub>1.9</sub> (0.4 ≤ <i>x</i> ≤ 1.0) magnetostrictive alloys were synthesized by arc-melting and subsequent high-pressure annealing. Measurements of x-ray diffraction, magnetization, and magnetostriction were performed on the alloys. Due to the effects of high-pressure, the alloys are stabilized in cubic Laves phase with MgCu<sub>2</sub>-type structure. The Curie temperature of the cubic Laves phase decreases linearly with the increase of <i>x</i>, which can be associated with the decreasing strength of 3<i>d</i>-4<i>f</i> coupling. With increasing <i>x</i> , the anisotropy of the alloys first decreases to a minimum at <i>x</i> = 0.6 and then increases. The magnetostriction of Sm<sub>1-</sub><i>x</i>Pr<i>x</i>Fe<sub>1.9</sub> changes signs from negative into a positive at <i>x</i> = 0.6 . The saturation magnetostriction increases with increasing <i>x</i>, while the sample with <i>x</i> = 0.9 shows a peak at low magnetic fields.
Study on the Preparation Technique and Magnetostriction of Sinter Tb0.7Pr0.3Fe1.80 Alloy
Mechanical alloying (MA) and subsequent solid sintering process was used to prepare the Pr-containing pseudobinary Tb0.7Pr0.3Fe1.80 alloys. The structural and magnetoelastic properties were in comparative investigated by means of x-ray diffraction and a standard strain technique for sinter and composite samples. The high Pr-content (Tb,Pr)Fe2 Laves phase with MgCu2-type structure for the composition Tb0.7Pr0.3Fe1.80 were synthesized by MA plus annealing at 500 °C.
Conserved Quantities of a Class of Nonlinear Difference-Difference Equations
Higher-order conserved quantities of a class of nonlinear difference-difference equations which are related to the discrete-time Toda equation are obtained using the Miura transformations.