| Garnet ferrite plays an important role owning to excellent spin magnetic properties,very narrow ferromagnetic resonance linewidth,high resistivity. Yttrium iron garnet (Y3Fe5O12) is one of the most important varieties in garnet ferrite, usually used as microwave device because of small magnetic loss in the microwave field.For microwave ferrite, Specific saturation magnetization Ms is one of the important parameters, substitution Y3+ in c site, Fe3+ in a and d site,molecular magnetic moment can be changed,thereby changing the specific saturation magnetization; moreover the calcination temperature affect garnet ferrite specific saturation magnetization. In this paper, rare earth Gd3+ ions and Ce3+ ions were selected to carry out single element and multiple elements subsititution,and the effect of different calcination temperatures on the magnetic properties of the samples was studied. In this paper, the experimental method is the sol-gel self-propagating method with the advantages of simple and good dispersion. Samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectrometer (FT-IR), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM).The main research works are as follows:1.Gd3+ ions substitut Y3+. XRD analysis showes that the samples are single phase garnet structure. With the increasing of Gd3+ ion content, the average grain size of the samples, lattice constants and density all increase. For the same amount of Gd3+ ion content, average grain size increases with the increasing of calcination temperature. FT-IR analysis showes that samples which Gd3+ ion content not equal to 0.0 occurred red-shift compared with YIG: When Gd3+ ion content is 0.0, the wavenumber of the tetrahedral Fe-O stretching vibration absorption peak is 565cm-1,600cm-1,658cm-1. When Gd3+ ion content is 1.0, the wavenumber of the tetrahedral Fe-O stretching vibration absorption peak is 560cm-1,597cm-1,653cm-1. VSM analysis showes that the specific saturation magnetization decreases from 28.15emu/g to 17.08emu/g with the increasing of Gd3+ ion content. For the same amount of Gd3+ ion content, the specific saturation magnetization increases slowly with the increasing of calcination temperature:when the calcination temperature is 800℃, the specific saturation magnetization of YIG is 26.49emu/g. when the calcination temperature is 1100℃, the specific saturation magnetization of YIG is 28.15emu/g. SEM and its statistical distribution show that the size distribution of Y2.5Gd0.5Fe5O12 is uniform and the degree of crystallinity is good, the average particle size is 3.514 μm.2.Ce3+ ions substitut Y3+. XRD analysis showes that the samples are single phase garnet structure. With the increasing of Ce3+ ion content, the average grain size of the samples decreases first and then increases. For the same amount of Ce3+ ion content, average grain size increases with the increasing of calcination temperature. FT-IR analysis showes that samples which Ce3+ ion content not equal to 0.00 occurred red-shift compared with YIG: When Ce3+ ion content is 0.00, the wavenumber of the tetrahedral Fe-0 stretching vibration absorption peak is 565cm-1,600cm-1,658cm-1. When Ce3+ ion content is 0.10, the wavenumber of the tetrahedral Fe-O stretching vibration absorption peak is 563cm-1,600cm-1,658cm-1. VSM analysis showes that the specific saturation magnetization has no significant change with the increasing of Ce3+ ion content. For the same amount of Ce3+ ion content, the specific saturation magnetization increases slowly with the increasing of calcination temperature: when the calcination temperature is 800℃, the specific saturation magnetization of Y2.99Ce0.01Fe5O12 and Y2.91Ce0.09Fe5O12 is 27.18emu/g and 28.02emu/g respectively, when the calcination temperature is 1100℃, the specific saturation magnetization of Y2.99Ce0.01Fe5O12 and Y2.91Ce0.09Fe5O12 is 28.09emu/g and 28.98emu/g respectively. SEM results showes reunite.3.Gd3+ ions and Ce3+ ions substitut Y3+. XRD analysis showes that the samples are single phase garnet structure. With the increasing of Gd3+ ion content, the lattice constants and density all increase, average grain size increases first and then decreases. For the same amount of Gd3+ ion and Ce+ ion content, average grain size increases with the increasing of calcination temperature. FT-IR analysis showes that samples which Gd3+ ion content not equal to 0.0 occurred red-shift compared with Y2.9Ce0.1Fe5O12:When Gd3+ ion content is 0.0, the wavenumber of the tetrahedral Fe-0 stretching vibration absorption peak is 563cm-1,600cm-1,658cm-1. When Gd3+ ion content is 0.9, the wavenumber of the tetrahedral Fe-0 stretching vibration absorption peak is 560cm-1,596cm-1,652cm-1. VSM analysis showes that the specific saturation magnetization decreases from 26.36emu/g to 17.45emu/g with the increasing of Gd3+ ion content. For the same amount of Gd3+ ion content, the specific saturation magnetization increases slowly with the increasing of calcination temperature: when the calcination temperature is 800℃, the specific saturation magnetization of Y2.9Ce0.1Fe5O12 is 26.75emu/g. when the calcination temperature is 1100℃, the specific saturation magnetization of Y29Ce0.1FesO12 is 28.26emu/g. SEM and its statistical distribution show that the size distribution of Y2.6Ce0.1Gd0.3Fe5O12 is uniform and the degree of crystallinity is good, the average particle size is 2.176μm. |
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