Home About us Contact
|
Home About us Contact | ||
|
|
||
Shielding Materials (shielding + material)
Selected AbstractsMicrostructure Control of Sintered Porous Yttria-Stabilized Zirconia as a Durable Thermal Shielding MaterialINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 3 2009Kazuya Sasaki The microstructure of a thermal shielding material affects its thermal conductivity and mechanical property. In this study, the effects of the sintering temperature and the polymethyl methacrylate powder as a pore-former on the microstructure of a sintered porous yttria-stabilized zirconia (YSZ), which is used as a durable thermal shielding material, were investigated. It became clear that the microstructure of the sintered YSZ could be controlled by the particle size and the amount of the pore-former and the sintering temperature. The effect of the yttria amount in the YSZ on the microstructure was also clarified. [source] Effect of weak reductant on properties of electroless copper polyacrylonitrile nanocomposites for electromagnetic interference shieldingJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2010Keng-Yu Tsao Abstract In this work, the electroless copper method with different reductant compositions (NaHSO3/Na2 S2O3·5H2O and Na2S2O3·5H2O) without sensitizing and activating, was used to deposit copper-sulfide deposition on the polyacrylonitrile (PAN) surface for electromagnetic interference (EMI) shielding materials. The weak reductant, NaHSO3, in the electroless copper method was used to control the phase of copper-sulfide deposition. The Cux(x=1,1.8)S was deposited on the PAN (CuxS-PAN) by reductant composition (NaHSO3/Na2S2O3·5H2O) and the Cux(x=1,1.8)S deposition of CuxS-PAN possesses three kinds of copper-sulfide phases (CuS, Cu1.75S and Cu1.8S). However, the electroless copper with reductant was only Na2S2O3·5H2O (without weak reductant, NaHSO3), the hexagonal CuS deposition was plated on the PAN (CuS-PAN) and increased the EMI shielding effectiveness of CuS-PAN composites about 10,15 dB. In this study, the best EMI SE of CuS-PAN and CuxS-PAN composites were about 27,30 dB and 15,17 dB respectively, as the cupric ion concentration was 0.24 M. The volume resistivity of CuS-PAN composite was about 1000 times lower than that of CuxS-PAN composite and lowest volume resistivity of CuS-PAN composites was 0.012 , cm, as the cupric ion concentration was 0.24 M. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Electromagnetic interference shielding by using conductive polypyrrole and metal compound coated on fabricsPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 8 2002C. Y. Lee Abstract Electromagnetic interference (EMI) shielding materials of complex type of conductive polypyrrole (PPy) as an intrinsically conducting polymer and silver-palladium (AgPd) metal compound coated on woven or non-woven fabrics are synthesized. From dc conductivity and SEM photographs of PPy/fabric complexes, we discuss charge transport mechanism and the homogeneity of coating on the fabrics. The EMI shielding efficiency of PPy/fabric and AgPd/fabric complexes is in the range of 8,,,80 dB depending on the conductivity and the additional Ag vacuum evaporation. The highest EMI shielding efficiency of PPy/fabric complexes vacuum-evaporated by Ag is ,80 dB, indicating potential materials for military uses. We propose that PPy/fabrics are excellent RF and microwave absorber because of the relatively high absorbance and low reflectance of the materials. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||