STRUCTURAL AND MAGNETOELASTIC PROPERTIES OF Y3Fe27.2Cr1.8 AND Ce3Fe25Cr4 FERROMAGNETIC COMPOUNDS.

The structural and magnetoelastic properties of polycrystalline samples of Y₃Fe_27.2Cr_1.8 and Ce₃Fe₂₅Cr₄ intermetallic compounds are investigated by means of X-ray diffraction, thermomagnetic, thermal expansion and magnetostriction measurements in the temperature range of 77-500 K under applied magnetic fields up to 1.5 T. The well defined anomalies observed in the linear thermal expansion coefficient curves are associated with the magnetic phase transitions and presence of small amounts of 1:12 phase in the Ce₃Fe₂₅Cr₄ sample; the latter is also confirmed by AC susceptibility measurements. For Y₃Fe_27.2Cr_1.8, saturation behavior is observed in the anisotropic magnetostriction isotherms near the magnetic ordering temperature (T_C), whereas for Ce₃Fe₂₅Cr₄ compound, saturation starts well below T_C. The additional anomalies observed in the volume magnetostriction isotherms of both compounds are explained based on the anisotropy field in the a-b plane and along the c-axis of the unit cell. [ABSTRACT FROM AUTHOR]