• 한국분말재료학회지
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• 제8권3호
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• pp.186-191
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• 2001

Several fabrication processes, corresponding nanostructural features and multifunctionality as well has been investigated for oxide ceramic based nanocomposites with metal nanodispersion (i.e., ceramic/metal nanocomposites). Transition metal (Ni, Co, etc) dispersed alumina and zirconia based nanocomposites have been synthesized by reducing and hot-press sintering of ceramic and metal oxide mixtures prepared by several method. Improved fracture strength (1.1 and 1.9 GPa for $Al_2O_3/Ni$ and $ZrO_2/Ni$ nanocomposites, respectively) of these composites have been achieved according to their nanostructures. In addition, ferromagnetic characteristic has been kept. The variation of magnetization with an applied stress has found to be more sensitive as smaller as the magnetic metal dispersion is. This result thus suggests the possibility of fracture and/or stress sensing of the composites by simple magnetic measurement.

• Elastomers and Composites
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• 제51권1호
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• pp.38-42
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• 2016

For improving the heat loss of a refrigerator around door gasket, it is very important to reduce the amount of rubber magnet used, of which thermal conductivity is much higher than the plastics, and enhancing the magnetic properties of rubber magnet itself is crucial for this. In the present study, therefore, a relationship between the optimum conditions of rubber magnet fabrication process and raw material compositions in the ferrite powder/CPE binder compounds was investigated for finding a way to enhance the magnetic properties of rubber magnet. Magnetic attraction forces of a sample rubber magnet was measured as function of distance, and thermal properties of the sample ferrite powder/CPE binder compound were analyzed with TG/DTA thermal analyzer. As a results, a rubber magnet strip with enhanced magnetic properties was expected to be fabricated, of which raw material compound was prepared by compounding with higher ferrite magnetic powder concentration.

• Carbon letters
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• 제11권2호
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• pp.117-121
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• 2010

The composites of alginate, carbon nanotube, and iron(III) oxide were prepared for the removal of heavy metal in aqueous pollutant. Both alginate and carbon nanotube were used as an adsorbent material and iron oxide was introduced for the easy recovery after removal of heavy metal to eliminate the secondary pollution. The morphology of composites was investigated by FE-SEM showing the carbon nanotubes coated with alginate and the iron oxide dispersed in the alginate matrix. The ferromagnetic properties of composites were shown by including iron(III) oxide additive. The copper ion removal was investigated with ICP AES. The copper ion removal efficiency increased greatly over 60% by using alginate-carbon nanotube composites.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2007년도 The 1st International Symposium on Advanced Magnetic Materials
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• pp.275-275
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• 2007

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2007년도 The 1st International Symposium on Advanced Magnetic Materials
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• pp.23.1-23.1
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• 2007

• 열처리공학회지
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• 제4권2호
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• pp.9-18
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• 1991

Among the many maunfactured processes of producing multi filamentary composites, in situ process is widely used owing tv its simplicity and easyness of mass production. In this study, the mechanical and electromagnetic properties of Cu-Fe composite materials was investigated. The tensile strength of the Cu-Fe wires increased as the Fe content and reduction ratio were increased. The Cu-30 wt%Fe composites had the best properties in terms of figure merits compared to the other Cu-Fe composites made in this study or the commercially manufactured 6/1 ACSR cables of Cu cable. The coercivity was decreased by increasing Fe content, but the squareness was increased greatly. As increasing reduction ratio, the coercivity and squareness increased up to the maximum points, and then decreased. For example, the maximum values were obtained at $0.09mm{\phi}$ for Cu-30 wt%Fe composites and at $0.066mm{\phi}$ for Cu-45 wt%Fe composites. The magnetic property of Cu-Fe wires produced by precipitation treatment was higher than that of Cu-Fe wires produced by thermomechanical treatment. By annealing Cu-Fe wires after drawing process, the coercivity, remanence and squareness were improved.

• Journal of Magnetics
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• 제17권4호
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• pp.308-315
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• 2012

Experimental investigations of the magnetization, magnetostriction and magnetoelectric (ME) effects were performed on sandwich - type Metglas/PZT/Metglas laminate composites. The results have been analyzed by taking into account the demagnetization contribution. The study has pointed out that the magnetic flux concentration is strongly improved in piezomagnetic laminates with a narrower width leading to a significant enhancement of the ME effects. The piezomagnetic laminates with the optimal area dimension were integrated to form a 2-D geomagnetic device, which simultaneously can precisely detect the strength as well as inclination of the earth's magnetic field. In this case, a magnetic field resolution of better than $10^{-4}$ Oe and an angle precision of ${\pm}0.1^{\circ}$ were determined. This simple and low-cost geomagnetic-field device is promising for various applications.

• Nano
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• 제13권11호
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• pp.1850125.1-1850125.12
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• 2018

To reduce the imbalance of impedance matching between the magnetic metal nanowires and free space, $Fe/TiO_2$ core/shell nanowire arrays with different diameters were fabricated in the templates of anodic aluminum oxide membranes by electrodeposition. The influences of the microstructure on the microwave absorption properties of the $Fe/TiO_2/Al_2O_3$ composites were studied by the transmission/reflection waveguide method. It was demonstrated experimentally that both the interfacial polarization and the diameter of the $Fe/TiO_2$ core/shell nanowires have critical effects on the microwave absorption properties. We also investigated the angle dependence of the microwave absorption properties. Due to the interfacial polarization and associated relaxation, the $Fe/TiO_2/Al_2O_3$ composites exhibited optimal microwave absorption properties when microwave propagation direction was accordant with the axis of the nanowires. Finally, we managed to obtain an optimal reflection loss of below -10 dB (90% absorption) over 10.2-14.8 GHz, with a thickness of 3.0 mm and the minimum value of -39.4 dB at 11.7 GHz.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2007년도 The 1st International Symposium on Advanced Magnetic Materials
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• pp.314.1-314.1
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• 2007

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2007년도 The 1st International Symposium on Advanced Magnetic Materials
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• pp.143.1-143.1
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• 2007