采用机械合金化法制备Al V Fe纳米粉末 ,通过测定M ssbauer效应 ,研究了不同球磨能量对制备Al V Fe纳米粉末的影响·结果表明 ,振动球磨与高能球磨所制备的Al V Fe纳米粉末结构均由非晶和α Al纳米晶组成 ,其非晶含量随着球磨能量...采用机械合金化法制备Al V Fe纳米粉末 ,通过测定M ssbauer效应 ,研究了不同球磨能量对制备Al V Fe纳米粉末的影响·结果表明 ,振动球磨与高能球磨所制备的Al V Fe纳米粉末结构均由非晶和α Al纳米晶组成 ,其非晶含量随着球磨能量的增加而有所不同·展开更多
用DSC技术和M ssbauer谱研究了颗粒弥散的快凝Al Fe V Si Nd合金薄带中纳米相的转变和相变动力学·结果表明 :快凝Al Fe V Si Nd纳米合金在加热过程中亚稳的Al8Fe4Nd相向α Al13 (Fe ,V) 3 Si相转变 ,并用Avrami公式计算了Al8Fe4Nd...用DSC技术和M ssbauer谱研究了颗粒弥散的快凝Al Fe V Si Nd合金薄带中纳米相的转变和相变动力学·结果表明 :快凝Al Fe V Si Nd纳米合金在加热过程中亚稳的Al8Fe4Nd相向α Al13 (Fe ,V) 3 Si相转变 ,并用Avrami公式计算了Al8Fe4Nd相的分解激活能Eα 为 1 61± 0 1 2eV·研究表明亚稳相Al8Fe4Nd向α Al13 (Fe,V) 3 Si相转变的过程是由原子体扩散和原位扩散共同控制的·展开更多
The effect of non-magnetic Al3+ ion doping on the magnetic properties of MnFe2-2xAl2xO4(0≤x≤0.4) spinel ferrites was studied using Mssbauer spectroscopy measurements at room temperature.From the Mssbauer study,i...The effect of non-magnetic Al3+ ion doping on the magnetic properties of MnFe2-2xAl2xO4(0≤x≤0.4) spinel ferrites was studied using Mssbauer spectroscopy measurements at room temperature.From the Mssbauer study,it is observed that the resolved hyperfine sextets are due to the distribution of Fe ions on the two sublattices of the spinel ferrites.The value of the isomer shift obtained from the fitting of the Mssbauer spectra indicates that Fe ions are in +3 state.A paramagnetic doublet is observed at degree of inversion x=0.4,superimposed on the hyperfine sextets,indicating that the super-exchange interaction A-B decreases due to the dilution of sublattice by Al3+ ions.The hyperfine magnetic field decreases at both interstitial sites of tetrahedral(A) and octahedral(B) with the increase in Al concentration.展开更多
文摘用DSC技术和M ssbauer谱研究了颗粒弥散的快凝Al Fe V Si Nd合金薄带中纳米相的转变和相变动力学·结果表明 :快凝Al Fe V Si Nd纳米合金在加热过程中亚稳的Al8Fe4Nd相向α Al13 (Fe ,V) 3 Si相转变 ,并用Avrami公式计算了Al8Fe4Nd相的分解激活能Eα 为 1 61± 0 1 2eV·研究表明亚稳相Al8Fe4Nd向α Al13 (Fe,V) 3 Si相转变的过程是由原子体扩散和原位扩散共同控制的·
基金Project supported by the Second Stage of Brain Korea 21 ProjectProject(RTI04-01-03) supported by the Regional Technology Innovation Program of the Ministry of Knowledge Economy (MKE),Korea
文摘The effect of non-magnetic Al3+ ion doping on the magnetic properties of MnFe2-2xAl2xO4(0≤x≤0.4) spinel ferrites was studied using Mssbauer spectroscopy measurements at room temperature.From the Mssbauer study,it is observed that the resolved hyperfine sextets are due to the distribution of Fe ions on the two sublattices of the spinel ferrites.The value of the isomer shift obtained from the fitting of the Mssbauer spectra indicates that Fe ions are in +3 state.A paramagnetic doublet is observed at degree of inversion x=0.4,superimposed on the hyperfine sextets,indicating that the super-exchange interaction A-B decreases due to the dilution of sublattice by Al3+ ions.The hyperfine magnetic field decreases at both interstitial sites of tetrahedral(A) and octahedral(B) with the increase in Al concentration.
