Thin alumina films have found applications in electronic circuits and cutting tools and have been recently explored as protective coatings against high temperature oxidation, but these studies have been relatively rare. In this study, amorphous alumina films 3.5 pm thick were produced by reactive sputtering on Co-30Cr-6Al-0.5Y coatings, using a pure aluminum target in Ar + 0 2 atmosphere. Isoth...

The paper reviews progress for a program of research on alumina ceramics processing, with particular reference to diffraction results achieved using tube x-rays, neutrons and synchrotron radiation. Outcomes from three related studies are examined. l Calcination of alumina hydrates to o-alumina via intermediate aluminas, including some new results indicating the co-existence of cubic and tetrago...

The present work deals with the mechanical properties of hybrid nanocomposites made epoxy/glass fibre dispersed different weight percentages nano-α-Al2O3 powder . nanoparticles were synthesized by a high energy ball milling technique (60 and 200 nm).. effect size content (wt%) on properties, such as tensile, flexural, interlaminar shear stress (ILSS) hardness was investigated. addition enhanced...

The stress behavior and the associated microstructure evolution of industrial Ti(C,N)/α-Al2O3 coatings subjected to thermal cycling are investigated by in situ energy dispersive synchrotron X-ray diffraction transmission electron microscopy. Temperature-dependent stresses changes microstructural parameters (domain size microstrain) analyzed measurements at different temperatures between 25 800 ...

Interpenetrating Al O /Al composites were created by liquid metal infiltration of alumina structures with three-dimensional periodicity produced by a robotic deposition method. Volume-averaged lattice strains in the alumina phase were measured by synchrotron X-ray diffraction at various uniaxial compression stresses up to 200 MPa. Load transfer was observed to occur from the aluminum to the alu...

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...

BACKGROUND Numerous studies have reported that microgrooves on metal and polymer materials can affect cell adhesion, proliferation, differentiation and guidance. However, our knowledge of the cell activity associated with microgrooves on ceramics, such as alumina, zirconia, hydroxyapatite and etc, is very incomplete, owing to difficulties in the engraving of microgrooves on the hard surface of ...

To understand the formation of structural isomers alumina (Al2O3) on surfaces Fe–Cr–Al alloys, cathodoluminescence (CL), X-ray photoelectron spectroscopy (XPS), and diffraction (XRD) were used. The alloys annealed under oxygen at a low partial pressure to focus initial Al2O3. XRD revealed that corundum (α-Al2O3) was predominantly formed alloy after annealing approximately 1100°C, whereas γ-Al2O...

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...

Allura red or Red 40 (R40) is a dye widely used in the food, textile, and pharmaceutical industries; it considered dangerous because soluble water, has high toxicity resistance to natural degradation. Several advanced wastewater treatments have been shown be effective for R40 removal but some of them present disadvantages such as by-products obtention, energy consumption, cost reactants process...