in this paper, penetration of high velocity impact of 4340 steel and tungsten carbide projectiles with specific shapes in to ceramic armor that includes 10 mm alumina (95%) is considered analytically and simulated with ls-dyna software. bernoulli equation used to consider the penetration velocity in ceramics, shows that the penetration is better and easier by increasing projectile density. the ...

The last two decades have seen a drastic increase in bacterial resistance to antibiotics and is a major concern for medical professionals world-wide. Metal oxide nanomaterials are currently the most promising tools applied as antimicrobial agents for diagnosis of diseases, drug delivery systems, sun screens and ceramics in biomedical and pharmaceutical arena. The antimicrobial activity of metal...

This study was conducted to enhance the tensile bond strengths of resin cements to zirconia ceramics. Fifty-six zirconia ceramic specimens (Cercon Base) and twenty-eight silica-based ceramic specimens (GN-1, GN-1 Ceramic Block) were air-abraded using alumina. Thereafter, the zirconia ceramic specimens were divided into two subgroups of 28 each according to the surface pretreatment; no pretreatm...

In this paper, a wax-based binder was developed for low-pressure injection molding of very fine (0,4 μm) average particle size alumina ceramic bodies. The major component used in the binder mixture was paraffin wax. The process of binder removal from the green ceramics presented several difficulties especially when the ceramic powder was very fine, and the pieces had large cross-section. The pr...

A light scattering model under the Rayleigh-Gans-Debye approximation has been developed for polycristalline alumina. The model states that transmittance of dense alumina ceramics basically depends not only on the maximum grain size but also on the preferential orientation of their c-axis, or texture. The effect of texture in transparency has been experimentally measured on several dense alumina...

The study of the adsorption and growth of metals on ceramics is a rapidly growing area, as these interactions are key to understanding many materials and processes used in modern technology. In particular, oxide-supported catalysts have been extensively studied, due to their widespread industrial applications. Knowledge of the role played by the underlying metal oxide in the reactivity of the m...

Recent research has been significantly increased our fundamental understanding of microwave interactions with materials. Thermal absorption has been demonstrated to result from simultaneous action of multiple dissipation mechanisms during processing. In addition, it has been conclusively established that strong microwave fields exert a non-thermal driving force during sintering. This force acts...

Abrasive machining in general and grinding in particular are processes, which increase their importance with high demands on accuracy of surface finish. The chip thickness is an evaluating variable to describe the quality of ground surface as well as the performance of the overall grinding system. A significant characteristic that distinguishes ceramics from metals is their low fracture toughne...

PURPOSE The purpose of this in vitro study is to examine the effects of a nano-structured alumina coating on the adhesion between resin cements and zirconia ceramics using a four-point bending test. MATERIALS AND METHODS 100 pairs of zirconium bar specimens were prepared with dimensions of 25 mm × 2 mm × 5 mm and cementation surfaces of 5 mm × 2 mm. The samples were divided into 5 groups of 2...