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Aluminum-silicon based hybrid composites reinforced with silicon carbide and graphite particles were prepared by liquid phase particle mixing (melt stirring) and squeeze casting. The thermal expansion and thermal conductivity behaviors of hybrid composites with various graphite contents (5.0; 7.5; 10 wt.%) and different silicon carbide particle sizes (45 µm and 53 µm) were investigated. Results indicated that increasing the graphite content improved the dimensional stability, and there was no obvious variation between the thermal expansion behaviors of the 45 µm and the 53 µm silicon carbide reinforced composites. The thermal conductivity of hybrid composites was reduced due to the enrichment of the graphite component.

DOI: http://dx.doi.org/10.5755/j01.ms.18.4.3093

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In this study, nanostructured ZnO thin film coatings produced by sol-gel method have been examined and characterized. ZnO thin film coatings synthesized by the preparation of ZnO sols in the liquid phase from homogeneous solutions with precursor of zinc acetate dihydrate (Zn(CH3COO)2 ·2H2O). Ethanol (C2H5OH) has been used as a solvent material and monoethanolamine (MEA) has been used as a complexing agent. The final solutions have 0.1, 0.3, 0.5, 0.7 and 1 molar concentrations. General morphologies and detailed structural characterizations have been obtained by using scanning electron microscope (SEM). Qualitative analyses of the synthesized coatings were performed using X-ray diffraction (XRD) and Raman spectroscopy. The Raman spectroscopy studies of precursor, solution and final products were carried out to investigate transformation of the chemical compounds from the initial material to the final coating.

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The aims of this work are synthesis of ZnO nanopowders and producing nanocomposites by mixing with carbon nanotubes. ZnO nanopowders have been synthesized by chemical precipitation route. Dierent amount of collected nanosized Zn-based precipitates and chemically oxidized carbon nanotubes powder have been mix together and annealed at 400 • C. Characterization of produced nanopowders and nanocomposites have been carried out by X-ray diractometer and scanning electron microscope.

In this study, tin/tinoxide (Sn/SnO2) nanocomposites thin lms were produced by thermal evaporation and plasma oxidation as anode materials for Li-ion batteries. To produce Sn/SnO2 thin lms, pure metallic tin (Sn) was thermally evaporated on the stainless steel substrates in argon atmosphere. The Sn lms were subjected to plasma oxidation process at oxygen/argon gas mixture. Three dierent plasma oxidation times (30, 45, and 60 min) were used to investigate oxidation kinetics and physical and microstructural properties. The surface properties were studied by scanning electron microscopy and atomic force microscopy. For structural analysis, X-ray diraction measurements were carried out. Sn/SnO2 coated stainless steel substrates were used as the working electrode in coin-type (CR2016) test cells. The energy storage capacity Sn/SnO2 electrodes were determined depending on the oxidation time and Sn:SnO2 ratio.

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