Gold nanoparticles, prepared by the Frens method, have been electrostatically assemblied onto mica substrates treated with different concentration of MnCl\-2 solution. The assemblies have been investigated by means of...Gold nanoparticles, prepared by the Frens method, have been electrostatically assemblied onto mica substrates treated with different concentration of MnCl\-2 solution. The assemblies have been investigated by means of atomic force microscopy(AFM). The immersing time of bare mica in Mn\+\{2+\} solution and the concentration of Mn\+\{2+\} solution both have significant effect on the assembled process of gold nanoparticulate monolayer. The coverage of gold particles shows periodical evolution on the immersing time of mica in MnCl\-2 solution. The higher is the concentration of MnCl\-2, the shorter is the time to attain maximum coverage. An ion\|exchanged and layer\|dissociated mechanism is put forth to explain the experimental results above.展开更多
Hybrid metal matrix composites are important class of engineering materials used in automotive, aerospace and other applications because of their lower density, higher specific strength, and better physical and mechan...Hybrid metal matrix composites are important class of engineering materials used in automotive, aerospace and other applications because of their lower density, higher specific strength, and better physical and mechanical properties compared to pure aluminium. The mechanical and wear properties of hybrid aluminium metal matrix composites were investigated. Mica and SiC ceramic particles were incorporated into A1 356 alloy by stir-casting route. Microstructures of the samples were studied using scanning electron microscope （SEM）. The chemical composition was investigated through energy dispersive X-ray （EDX） detector. The results indicate that the better strength and hardness are achieved with A1/10SiC-3mica composites. The increase in mass fraction of mica improves the wear loss of the composites.展开更多
文摘Gold nanoparticles, prepared by the Frens method, have been electrostatically assemblied onto mica substrates treated with different concentration of MnCl\-2 solution. The assemblies have been investigated by means of atomic force microscopy(AFM). The immersing time of bare mica in Mn\+\{2+\} solution and the concentration of Mn\+\{2+\} solution both have significant effect on the assembled process of gold nanoparticulate monolayer. The coverage of gold particles shows periodical evolution on the immersing time of mica in MnCl\-2 solution. The higher is the concentration of MnCl\-2, the shorter is the time to attain maximum coverage. An ion\|exchanged and layer\|dissociated mechanism is put forth to explain the experimental results above.
文摘Hybrid metal matrix composites are important class of engineering materials used in automotive, aerospace and other applications because of their lower density, higher specific strength, and better physical and mechanical properties compared to pure aluminium. The mechanical and wear properties of hybrid aluminium metal matrix composites were investigated. Mica and SiC ceramic particles were incorporated into A1 356 alloy by stir-casting route. Microstructures of the samples were studied using scanning electron microscope （SEM）. The chemical composition was investigated through energy dispersive X-ray （EDX） detector. The results indicate that the better strength and hardness are achieved with A1/10SiC-3mica composites. The increase in mass fraction of mica improves the wear loss of the composites.
