This paper considers the degradation of alumina and zirconia toughened alumina vs. alumina for hip implants. The materials are as assumed to be load bearing surfaces subjected to shocks in wet conditions. The load is a peak of force; 9 kN was applied over 15 ms at 2 Hz for 800,000 cycles. The volumetric wear and roughness are lower for ZTA than for alumina. The long ZTA ageing did not seem to h...

Anodic porous alumina has been widely investigated and used as a nanostructure template in various nanoapplications. The porous structure consists of numerous hexagonal cells perpendicular to the aluminum substrate and each cell has several tens or hundreds of nanoscale pores at its center. Because the nanomorphology of anodic porous alumina is limited by the electrolyte during anodizing, the d...

Experimental researches on adsorptive capacity of activated alumina, silica sand and anthracite coal for phosphorus were conducted. Results showed that performances of three filter media were all in line with Langmuir isotherm, and activated alumina adsorptive performance was much better than silica sand and anthracite coal for phosphorus removal. The adsorptive capacity of activated alumina, s...

Mono-phase bio-ceramics (alumina and zirconia) are widely used as femoral heads in total hip replacements (THR) as an alternative to metal devices. Unfortunately, the orthopaedic community reports significant in-vivo failures. Material scientists are already familiar with composites like alumina zirconia. Since both are biocompatible, this could prove to be a new approach to implants. This pape...

There are no appreciable amounts of nickel resources in Iran; therefore, secondary resources of this element are to be more considered in future. Spent nickel catalysts that are used in various industrial processes are one of them. For example nickel catalyst that is used in hydrogenation of edible oil have large amounts of nickel and they are generally supported on porous materials like silica...

Simple nanoporous alumina matrix modification procedure, in which the electrically highly insulating alumina barrier layer at the bottom of the pores is replaced with the conductive layer of the gold beds, was described. This modification makes possible the direct electron exchange between the underlying aluminum support and the redox species encapsulated in the alumina pores, thus, providing t...

INTRODUCTION Incorporating a feldspar chemical bond between alumina filler particles is expected to increase the wear-resistant and flexural strength properties. AIMS AND OBJECTIVES An investigation was carried out to evaluate the influence of the feldspar chemical bonding between alumina filler particles on wear and flexural strength of experimental alumina/feldspar dental composites. It was...

Hydroxyapatite/alpha-alumina composites were prepared by means of high-energy vibratory ball milling. The effect of the addition of alumina, from 5 to 25 wt%, was investigated. x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) results indicated thathydroxyapatite andaluminawere themajorphases aftermechanicalmilling and only small peak shifts were observed. Transmission...