• Journal of the Korean Magnetics Society
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• v.2 no.3
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• pp.211-215
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• 1992

The temperature-dependent saturation magnetization curves of amorphous $Fe_{80-x}Co_xB_{20}$ (8 ${\le}$ x ${\le}$ 40, the step of x is 8) alloys were measured using a vibrating sample magnetometer from 77 K up to 1000 K. Curie temperature and the Bloch coefficient were estimated from the saturation magnetization curves. The low temperature dependence of magnetization is in good agreement with Bloch relation, $M_s(T)$=$M_s(O)$ (1-$BT^{3/2}$ - ${\cdots}.$). The spin wave stiffness constant, tne range of the exchange interaction, and the probable atomic spin were calculated from the saturation magnetization values.

• Journal of Magnetics
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• v.16 no.3
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• pp.308-311
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• 2011

In order to obtain mono-dispersed Fe NPs with high saturation magnetization, quantitative analysis method to investigate the growth dynamics of the Fe NPs synthesized by a conventional thermal decomposition method has been developed. As a result, fast nucleation process promotes formation of ~4 nm of initial nucleus with a non-equilibrium phase, resulting in low saturation magnetization. And slow particle growth with atomic-scaled surface precipitation mode (< 100 atoms/($min{\cdot}nm^2$)) can form the growth layer on the surface of initial nucleus with high saturation magnetization (~190 emu/$g_{Fe}$) as an equilibrium a phase of Fe. Therefore, higher stabilization of small initial nucleus generated just after the injection of $Fe(CO)_5$ should be one of the key issues to achieve much higher $M_s$ of Fe NPs.

• Journal of Magnetics
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• v.21 no.3
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• pp.315-321
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• 2016

M-Zn (M = Sb, V, Nb) substituted M-type strontium hexaferrites were prepared by a ceramic method. The phase composition, morphology and magnetic properties were studied by x-ray diffractometry, scanning electron microscopy and vibrating sample magnetometry. Saturation magnetization increases with a substitution up to 75.0 emu/g (2.5 % higher compared to unsubstituted hexaferrite) and then decreases with a further substitution. A coercive field of substituted hexaferrite powders with highest saturation magnetization is more than 3 kOe. Substituted strontium hexaferrite powders prepared in this work are a rare example of high $M_S$ compositions without doping rare-earth elements and would be a promising candidate for a permanent magnet application.

• Journal of the Korean Magnetics Society
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• v.9 no.4
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• pp.173-176
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• 1999

Errors of saturation magnetization and magnetocrystalline anisotropy constant determined by magnetization curve of magnetically aligned unixial power were analyzed. In case of alignment factor ${\Theta}_0=10{\circ}$, magnetic constant errors of $Nd_2Fe_{14}B$ were calculated to be error of $M_S{\risingdotseq}1{\%}\;and\;error\;of\;K_1{\risingdotseq}13\;{\%}$, respectively, and magnetic constant errors of Ba-ferrite were calculated to be error of $M_S{\risingdotseq}1{\%}\;and\;error\;of\;K_1{\risingdotseq}17\;{\%}$. In this method, $M_s$ was found to be determined with high accuracy. High alignment is desirable for high accuracy.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.92-93
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• 2002

The substituted lithium ferrites combine useful ferromagnetic properties with high Curie temperature ranging from 55$0^{\circ}C$ to 85$0^{\circ}C$, [1] high saturation magnetization, [2] and low microwave dielectric loss.[3] Saturation magnetization of (Z $n_{1-x}$ F $e_{x}$)A[L $i_{0.5x}$F $e_{ 2-0.5x}$]$_{B}$ $O_4$ increased with zinc concentration, followed by a decrease at x = 0.7.[4] This is attributed to a dilution of the A-site with zinc which initially causes an increase in saturation magnetization due to the dominance of the B-site. (omitted)d))d)d))

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.496-499
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• 1995

Amorphous $Co_{80+x}TM_{12}B_{8-x}$ (TM = Ti, Zr, Hf, Nb and x = 0, 2, 4 at%) alloys were prepared by single roll melt spinning technique. Saturation magnetization of the amorphous ribbons was measured by SQUID and vibrating sample magnetometer from 5 to 800 K under applied fields up to 10 kOe. Typical thermo-magnetization curves were observed and the average values of the spectroscopic splitting g factor were estimated from the ferromagnetic resonance curve. For all the amorphous alloys studied here the saturation magnetization in the temperature range 5 K up to about $0.3T_{c}$ can be described by the Bloch relation: $M_{s}(T)\;=\;M_{s}(0)(1-BT^{3/2}-CT^{5/2})$. From the values of $M_{s}(0)$, B and spectroscopic splitting g factor the spin wave stiffness constants were calculated.

• Journal of the Korean Magnetics Society
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• v.1 no.2
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• pp.55-59
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• 1991

The temperature-dependent magnetization curves of amorphous Fe-Co-(Nd, Sm, Gd, Tb)-B alloys were measured using a vibrating sample magnetometer from 77 K up to 900 K. The spin wave stiffness constants and the range of the exchange interaction were calculated from the saturation magnetization values at 0 K. Curie temperatures and the Bloch coefficients estimated from the saturation magnetization curves. The low temperature dependence of magnetization is in good agreement with Bloch relation, $M_{s}(T)=M_{s}(O)(1-BT^{3/2}-CT^{5/2})$. The spin wave stiffness constant and the range of exchange interaction are decreased by substitution of heavy rare earth (Tb, Gd).

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.214-215
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• 2002

High saturation magnetization (B$\_$s/) and excellent high frequency characteristics of magnetic thin films has been recognized as the most important requirement for further miniaturization and higher frequency operation in magnetic devices, such as magnetic heads and magnetic sensors. Up to now, Fe-X-N (X =Ti, Hf, and Al etc.) films with B$\_$s/ of 15 ∼ 19 kG and coercivity (H$\_$c/) of 0.5 ∼ 5.0 Oe have been successfully fabricated and proven to satisfy various requirements as a potential candidate for thin film head materials. (omitted)

• Progress in Superconductivity and Cryogenics
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• v.7 no.2
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• pp.7-10
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• 2005

The magnetic properties of a series of both annealed (biaxially textured) and as-rolled (non-textured) Ni-xW alloy tapes with compositions x = 0,1,3, and 5 at.$\%$, were studied. Characterization methods included XRD analyses to investigate the biaxial cube texturing of the annealed Ni-W alloy tapes and studies of the magnetization M for both annealed and as-rolled Ni-W alloy tapes. Both the isothermal mass magnetizations M(H) of a series of samples at different fixed temperatures and M(T) in fixed field, employing a PPMS-9 (Quantum Design), were measured. The Ni-W alloys have shown much reduced ferromagnetism as W-content x increases. Both the saturation magnetization Msat and Curie temperature Tc decrease linearly with W-content x, and both Msat and Tc go to zero at critical concentration of Xc - 9.50 at. $\%$ W.

• 한국초전도학회:학술대회논문집
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• v.15
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• pp.33-33
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• 2005