The effect of sintering temperature on the structure, magnetic transition and magnetic entropy of La0.6Ca0.4MnO3 manganite was studied. It was observed that this compound belongs to the orthorhombic structure with the...The effect of sintering temperature on the structure, magnetic transition and magnetic entropy of La0.6Ca0.4MnO3 manganite was studied. It was observed that this compound belongs to the orthorhombic structure with the Pnma space group without any impurity phase. The effect of sintering temperature on the Curie temperature(TC) was studied. The small increment in TC is found with increasing the sintering temperature. The magnetocaloric study exposes a quite large change of the magnetic entropy, which varies with sintering temperature. For an applied magnetic field of 3 T and sintering temperature of 1300 °C, the relative cooling power(RCP) is 89 J/kg. As a result, the studied compound can be considered as potential material for magnetic refrigeration near and below room temperature.展开更多
Co-based Co63Fe4B22.4Si5.6Nb5 amorphous ribbons with a width of 150 μm and a thickness of 50 μm were prepared by single-roller melt-spinning process.The giant magneto-impedance(GMI) effect of the stress-joule-heated...Co-based Co63Fe4B22.4Si5.6Nb5 amorphous ribbons with a width of 150 μm and a thickness of 50 μm were prepared by single-roller melt-spinning process.The giant magneto-impedance(GMI) effect of the stress-joule-heated ribbons under applied tensile stress ranging from 37 to 148 MPa was investigated.Experimental results show that the spectra of GMI ratio vs.external direct current(dc) field(Hex) of the samples changes dramatically with annealing tension() and driving frequency.The single-peak(SP) GMI curve with maximum GMI ratio of 260% and magnetic field sensitivity of 52%/Oe was obtained in the sample applied tensile stress of 74 MPa at frequency of 3.6 MHz.A three-peak behaviour appeared in the samples under σ of 111 and 148 MPa.The uncommon three-peak behaviour was attributed to several factors,which effectively originated from the balance between domain-wall movement and magnetization rotation.展开更多
基金Project(2012-RIAIB300784) supported by Basic Science Research Program through the NRF of Korea funded by the MESTProject(2012HIB8A2026212) supported by the MEST and NRF of Korea the Human Training Project for Regional Innovation
文摘The effect of sintering temperature on the structure, magnetic transition and magnetic entropy of La0.6Ca0.4MnO3 manganite was studied. It was observed that this compound belongs to the orthorhombic structure with the Pnma space group without any impurity phase. The effect of sintering temperature on the Curie temperature(TC) was studied. The small increment in TC is found with increasing the sintering temperature. The magnetocaloric study exposes a quite large change of the magnetic entropy, which varies with sintering temperature. For an applied magnetic field of 3 T and sintering temperature of 1300 °C, the relative cooling power(RCP) is 89 J/kg. As a result, the studied compound can be considered as potential material for magnetic refrigeration near and below room temperature.
基金supported by the National Natural Science Foundation of China(Grant Nos.50825103 and 51271194)Ningbo Science and Technology Innovation Team(Grant No.2011B82004)Equipment Project for Research of the Chinese Academy of Sciences(Grant No.Y2010010)
文摘Co-based Co63Fe4B22.4Si5.6Nb5 amorphous ribbons with a width of 150 μm and a thickness of 50 μm were prepared by single-roller melt-spinning process.The giant magneto-impedance(GMI) effect of the stress-joule-heated ribbons under applied tensile stress ranging from 37 to 148 MPa was investigated.Experimental results show that the spectra of GMI ratio vs.external direct current(dc) field(Hex) of the samples changes dramatically with annealing tension() and driving frequency.The single-peak(SP) GMI curve with maximum GMI ratio of 260% and magnetic field sensitivity of 52%/Oe was obtained in the sample applied tensile stress of 74 MPa at frequency of 3.6 MHz.A three-peak behaviour appeared in the samples under σ of 111 and 148 MPa.The uncommon three-peak behaviour was attributed to several factors,which effectively originated from the balance between domain-wall movement and magnetization rotation.