in the present investigation surface modification of silica nanoparticles by alumina was carried out by sol-gel process. fourier transform infrared (ftir) and x-ray fluorescence (xrf) confirmed the synthesis of silica and the surface modification as alumina is anchored to silica surface. field emission scanning electron microscopy (fesem) and transmission electron microscopy (tem) investigation...

Polyurethane-based micro- and nano-hybrid composites were produced with controlled porosity to be used as obturation materials. In addition to hydroxyapatite (HAp) micro-particles in the composites, two different ceramics particle types were also added: alumina micro-particles and silica nano-particles. Particles of different sizes provide the materials with improved mechanical properties: the ...

In-situ alumina-zirconia composite bodies were fabricated by heat treatment of gibbsite-zircon-kaolinite mixture at 1450℃. The current research investigated crystallization behavior and mechanical properties of the mentioned mixture in the presence of 5 wt.% MgO as an additive. X-ray diffraction (XRD) results showed that alumina, zirconia, and magnesium aluminosilicate were crystallized during ...

Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the e...

Partially stabilized zirconia (PSZ) agglomerate toughened alumina has been prepared by the "deflocculation-flocculation" technique, using 2 and 3 mol. % Y2O3-doped zirconia powders. Samples containing up to about 30 vol.% zirconia were obtained. The resulting microstructure seems to be mainly influenced by the physical properties of the starting powders, e.g. agglomerate size and the specific s...

The tensile properties of an aluminium-based metal matrix composite reinforced with a-alumina platelets were investigated from an experimental and a theoretical point of view. An increase in Young modulus, 0,2% proof stress, flow stress and ultimate tensile strength was observed over the unreinforced metal. These improvements were obtained at the expense of the tensile ductility. The experiment...

Abstract In this study, copper matrix composites were prepared using the cold and hot pressing technique then investigated to select suitable one for self-lubricating applications. A hybrid of alumina molybdenum disulfide with a 1:1 ratio by mechanical milling 40 h was proceeded peel cover particles their layers. Three different samples like Cu, Cu/10 Al 2 O 3 , Cu/hybrid 20(Al –MoS ) mixed 15 ...

Alumina is one of the most widely used adsorbent for removal of dissolved pollutants from waste water. Various chemical species, especially ions, are known to be adsorbed onto alumina. On the other hand, alumina is a typical support for catalysts. Many kinds of metal supported catalysts are prepared using alumina as their support. These two roles of alumina, i.e., as adsorbent and support, are ...