Magnetic properties of Sm2Co17-xCrx (0 <= x <= 3.0) compounds

https://profdoc.um.ac.ir/articles/a/1016022.pdf

Influence of Si and Co substitutions on magnetoelastic properties of R2Fe17 (R=Y, Er and Tm) intermetallic compounds

Spin reorientation and magnetic anisotropy in Y2Co17−xCrx (x = 1.17–3.0) compounds

Structure and magnetic properties of Gd2Co17−xCrx (1.17 ≤ x ≤ 3.0) compounds

The effect of Ga∕Al substitution on the structural and magnetic properties of YGdFe17 has been investigated. A structural transformation from hexagonal to rhombohedral has been observed. The saturation magnetization increases up to x=1 (Ga)∕2 (Al) and then decreases with further increase of x. Curie temperature increases from 476 K for YGdFe17 to 595 K for YGdFe14Ga3 and 495 K for YGdFe14Al3 and decreases with further substitution of Ga∕Al. The easy magnetization direction is planar up to x=6 for Ga- and 7 for Al-substituted compounds and shifts to along c axis for x=8.

Magnetic properties of YGdFe17−x(Ga,Al)x (x=0–8)

Structural and magnetic properties of ErPrFe17−xMx (M=Ga, Si; x=0–3.5)

Magnetic properties of (Sm0.5Tb0.5)2Fe17−xGax [mentioned subsequently as SmTbFe17−xGax] have been investigated. All the compounds have formed in rhombohedral Th2Zn17 structure with traces of α‐Fe. The saturation magnetization decreases with increasing x and is attributed to the modification of the density of states of 3d band due to the low lying 3p band of Ga. The increase of Curie temperature up to x=3 and subsequent decrease is explained on the basis of band narrowing. The easy direction of magnetization is in the ab plane up to x=5 and changes along the c axis for x=7.

Magnetic properties of SmTbFe17−xGax [0⩽x⩽8]

The structural and magnetic properties of SmTbFe17−xAlx (x=0–8) and SmTbFe17−xSix (x=0–3.5) were investigated by x-ray-diffraction and magnetization studies. All the compounds stabilize in rhombohedral structure. The lattice parameters are found to increase with Al substitution whereas they are found to decrease with Si substitution. The rates of the decrease of saturation magnetization (Ms) value with the substitution of Al and Si are almost the same. The easy direction of magnetization (EMD) is in the ab plane up to an Al concentration of x=7 and has a tendency to shift towards the c axis at x=8. All the compounds with Si are seen to have the EMD in the ab plane. Electron-magnon scattering is seen to contribute to the electrical resistivity in both Al- and Si-substituted compounds; in the temperature range of 30–60K and at higher temperatures, scattering due to phonons is observed.

Effect of Al and Si substitutions on the magnetic properties of SmTbFe17

The alloys ErPrFe 17− x Ga x and ErPrFe 17− x Si x ( x =0–3.5) have been prepared and their structure and magnetization have been investigated. Powder X-ray diffraction patterns show that these compounds crystallize in hexagonal Th 2 Ni 17 (2:17) structure. The lattice parameters are found to increase as the Ga concentration is increased and decrease with increase of Si concentration. The saturation magnetization ( M s ) measured at 20 K is found to increase initially and then decrease as the Ga and Si concentration are increased beyond 0.1. The Curie temperatures of ErPrFe 15 Ga 3.5 and ErPrFe 15 Si 3.5 are 528 and 537 K which are 241 and 250 K, respectively, higher than that of the parent compound ErPrFe 17 and this has been explained on the basis of band model. The X-ray diffraction patterns taken for the magnetically aligned samples suggest that the easy magnetization direction (EMD) is in the basal plane in the Si substituted samples whereas in the case of the Ga substituted samples the EMD tend to be away from the basal plane. The anisotropy fields ( H A ) calculated from the magnetization measurements on aligned samples show that in the case of the Ga substituted compounds there is a significant increase in H A compared to the ones that are seen in the Si substituted compounds.

V. S. Murty

Papers

Structural and magnetic properties of ErPrFe17−xMx (M=Ga, Si; x=0–3.5)

Magnetic properties of YGdFe17−x(Ga,Al)x (x=0–8)

Magnetic properties of SmTbFe17−xGax [0⩽x⩽8]

Effect of Al and Si substitutions on the magnetic properties of SmTbFe17

Structural and Magnetic Properties of ErPrFe17‐xMx (M: Ga, Si; x = 0—3.5).