Surface topography and defect structures associated with ballistic impact in a commercial 94 percent alumina ceramic armor are described. Fracture surfaces were examined by scanning electron microscopy, augmenting previous replication electron fractography studies. Direct transmission electron microscopy was employed in characterizing defect structures in extracted fracture fragments on replica...

Ultralong Si3N4 nanowires (NWs) were successfully synthesized with size controlled in N2 gas by using an efficient method. The diameters of the Si3N4 NWs increased when the flow rate of N2 gas increased, with average diameters of 290 nm from flow rates of 100 ml/min, 343 nm from flow rates of 200 ml/min and 425 nm from flow rates of 400 ml/min. Young's modulus was found to rely strongly on the ...

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...

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...

BACKGROUND Ceramic-on-ceramic couplings are attractive alternative bearing surfaces that have been reported to eliminate or reduce problems related to polyethylene wear debris. Disappointing experiences with alumina ceramic bearings in the past have led to many improvements in the manufacture and design of ceramic implants. The purpose of the present study was to report the results of contempor...

objective: to date, several scaffolds have been fabricated for application in bone tissue repair. however, there remains a need for synthesis of scaffolds with better mechanical properties, which can be applied to defects in weight-bearing bones. we constructed a composite ceramic bioscaffold of hydroxyapatite-alumina and silicon carbide (ha-al2o3- sic) to take advantage of the mechanical prope...

Atmospheric plasma spraying (APS) is a well established process for preparing ceramic coatings. In this process, powder particles injected into the plasma jet are heated and accelerated simultaneously in the plasma stream and are deposited in molten or semi-molten droplets conditions onto a prepared substrate. During droplet impingement, these molten droplets rapidly solidify to form single spl...

Alumina-rich iron ore is a widely existed polymetallic deposit in the nature, and it has a high comprehensive utilization value. Because the alumina and iron contents of alumina-rich iron ore vary from each other, there are many different measures and processes to recover iron and alumina from the various kinds of alumina-rich iron ore. In the blast furnace (BF) ironmaking process, the alumina ...

• Significant effect of the method catalyst preparation on stability. Mechanochemically prepared catalysts showed superior 20 wt% NaAlO2/Al2O3 is most stable with 96% glycerol carbonate yield. Al2O3 provided highest stability compared to other metal oxide supports. Glycerol, an important by-product from biodiesel production, has significant potential as platform chemical several different pathw...

BACKGROUND While most reports of component fracture following alumina-on-alumina total hip arthroplasty have involved the acetabular liner, few have involved fracture of the alumina femoral head. In the present multicenter study, we investigated ceramic head fractures in a cohort of patients who underwent third-generation alumina-on-alumina total hip arthroplasty. METHODS We performed a retro...