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Trans.Nonferrous Met.Soc.China30(2020)1895−1903
Effect of chromium substitution on structural,electrical and
magnetic properties of NiZn ferrites
Guang-sheng LUO1,2,Yu-hao HONG1,Wei-ping ZHOU1,2,
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Zhen-zhi CHENG1,2,Chi-cheng MA1,Zhong-kai WU1,Huan-huan HUANG1
关于教师节的征文1.School of Materials Science and Engineering,Nanchang University,Nanchang330031,China;
2.National Laboratory of Solid State Microstructures,School of Physics,Nanjing University,Nanjing210093,China
Received15August2019;accepted28May2020
Abstract:Ni0.5Zn0.5Fe2−x Cr x O4(0≤x≤0.5)ferrites were successfully prepared by conventional solid state reaction method to investigate the effect of chromium substitution on the structural,electrical and magnetic properties.X-ray powder diffraction results demonstrate that all the prepared samples are well crystallized single-pha spinel structures without condary pha.As chromium concentration increas,the lattice parameter and crystallite size gradually decrea.The magnetic measurement indicates that saturation magnetization is substantially suppresd by Cr3+doping, changing from73.5A·m2/kg at x=0to46.3A·m2/kg at x=0.5.While the room-temperature electrical resistivity is more than four orders of magnitude enhanced by Cr3+substitution,reaching up to1.1×108Ω·cm at x=0.5.The dielectric constant monotonously decreas with rising frequency for the ferrites,showing a normal dielectric dispersion behavior.The compositional dependence of diel
ectric constant is inver with that of electrical resistivity,which originates from the reduced Fe2+/Fe3+electric dipole number by doping,indicating inherent correlation between polarization and conduction mechanism in ferrite.
发面烧饼
中国工科大学排名Key words:NiZn ferrite;chromium doping;electrical resistivity;dielectric properties;saturation magnetization
1Introduction
正宗粉蒸肉Acquiring high performance soft magnetic materials is of demanding needs for the electrified world due to their widespread application in power electronics,electrical machines,microwave devices, transformer core,multilayer inductor,automatics, and computer facilities,etc[1−3].Spinel ferrite is one of the important soft magnetic materials that are suitable for magnetic and electronic device applications,which have attracted substantial attention for decades[4−8].In addition to their excellent magnetic characteristics,high electrical resistivity,low eddy current and reduced dielectric loss in spinel ferrites further widen their application to microwave frequencies[9].The crystal structure of spinel ferrite is commonly face-centered cubic structure with space group Fd3m,which is typically expresd in the molecular formula of AB2O4. In this structure,A and B reprent four-fold tetrahedr翩翩组词
al lattice sites(A)and six-fold octahedral lattice sites(B)in the cubic clo-packed framework compod by oxygen ions[4]. According to the distribution of cations on the crystallographic site,the spinels can be categorized as normal,inver and mixed spinel.Among the spinel family,the mixed NiZn ferrites have been intensively scrutinized for their outstanding and versatile properties,including high electrical
Foundation item:Project(11604147)supported by the National Natural Science Foundation of China;Project(M32048)supported by the Foundation of National Laboratory of Solid State Microstructures,China;Project(20142BBE50014)supported by the
Jiangxi Province Key Projects of Science and Technology Support Plan,China
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Corresponding author:Wei-ping ZHOU;Tel:+86-791-83968964;E-mail:**************
DOI:10.1016/S1003-6326(20)65348-1
