Papers by Author: Fernand D.S. Marquis

Abstract: In recent years considerable attention has been dedicated to renewal power sources, such as wind power. This work was carried out in order to develop a small wind turbine of 1-10kW power generation capability. This wind turbine is designed to be energetically more efficient by 30-50% and having a lesser specific cost (by 25-30%). This work focused on the development of composite materials for application on the blades in the wind generator. In this paper we present the results of the research work done on the development of flexible technology for the fabrication matrix-epoxy resin based hybrid composites, reinforced with carbon, basalt and glass fibers. These new composite and hybrid materials were fabricated using epoxy matrixes. These matrices were reinforced with basalt and carbon fibers of different content and strengthened by mullite-like crystals. The basalt fibers for composite reinforcing were prepared from raw materials, with chemical composition: SiO2-15.3%; CaO-10.8%; Na2O-4.2%; MgO-8.8%; Fe2O3-12.1%; MnO-0.7%; TiO2-0.7%. The properties of new composites developed depend on the content and architecture of reinforcing components and are: tensile strength-(0.012-1.590)GPa; compression strength-(0.078-0.656)GPa; modulus of elasticity-(8.4-162.9)GPa; Poisson ratio-(0.015-0.559). The variation of strength and elastic characteristics under tension and compression of the new composites are presented.

Abstract: Owing to their exceptional stiffness, strength, thermal and electrical conductivity, carbon nanotubes have the potential for the development of nano composites materials for a wide variety of applications. In order to achieve the full potential of carbon nanotubes for structural, thermal and electrical multifunctional applications, both single wall carbon nanotubes (SWNTs), double wall nanotubes (DWNTs) and multi wall nanotubes (MWNTs) need to be developed into fully integrated carbon nanotube composites. Full integration of nanotubes requires their development beyond conventional composites so that the level of the non-nanotube material is designed to integrate fully with the amount of nanotubes and where the nanotubes are part of the matrix rather than a differing component, as in the case of conventional composites. In order to advance the development of multifunctional materials from nanotubes, this research is focused on the simultaneous control of structural properties, thermal and electrical conductivity of fully integrated carbon nanotube composites. These are hybrid material systems designed to surpass the limits of rule of mixtures engineering and composite design. The goals are to implement designs to fully mimic the properties of carbon nanotubes on larger scales for enhanced thermal and electrical management in addition to controlled strength and toughness. These new approaches involve, functionalization, dispersion, stabilization, alignment, polymerization and reaction bonding, in order to achieve full integration. Typical examples of polymeric and ceramic matrices, as well as other material systems are presented and discussed.

Abstract: Results of the investigation of composite materials of new type, based on basalt fiber and polyester resin, are presented, in particular, a long-term resistance of the material in corrosive media: in caustic soda as well as in sulphuric and nitric acids of 1% concentration has been estimated. The service life of given composite is recommended in above-mentioned media.