Abstract Alumina is often used for electrical insulation. However, different material systems promise to increase the insulation due their characteristics. Because of process properties including high cooling rates, thermally sprayed coatings generally differ from sintered material, which also effect properties. Within this study, are analyzed via impedance spectroscopy evaluate capacitive and ...

Thermally sprayed ceramic coatings such as alumina have a specific microstructure characterized by porosity and microcracks. In addition, process-related phase transformation from α-Al2O3 to γ-Al2O3 typically occurs, which affects the properties of compared sintered alumina. previous study, simultaneous additions Cr2O3 TiO2 already extended improved property profile pure coating (i.e., sliding ...

The purpose of this study was to evaluate and compare the bond strengths between resin composite veneer and laser-sintered cobalt-chromium (Co-Cr) alloy with and without retention devices (Laser-R and Laser-N respectively). Cast Co-Cr alloy with and without retention devices (Cast-R and Cast-N respectively) were also prepared for fabrication technique comparison. Disk-shaped Co-Cr alloy specime...

We measured the complex capacitance C( f ) of ITO/sol-gel alumina/Al capacitors deposited on glass (and some on stainless steel foil) in the frequency range 15 Hz–10 MHz. The sol-gel films were deposited by dip-coating and following a two step process. The capacitance C( f ) found was much higher than that of a pure Al2O3-film due to the remaining porosity of the film and the uptake of H2O from...

The densification behavior, microstructure and mechanical properties of bulk TiB₂-based ceramic composites, fabricated using the spark plasma sintering (SPS) technique with elements of (Fe-Ni-Ti-Al) sinter-aid were investigated. Comparing the change of shrinkage displacement of pure TiB₂ and TiB₂-5 wt% (Fe-Ni-Ti-Al), the addition of elements Fe-Ni-Ti-Al into TiB₂ can facilitate sintering of the...

Stabilization efficiencies of spinel-based construction ceramics incorporating simulated nickel-laden waste sludge were evaluated and the leaching behavior of products investigated. To simulate the process of immobilization, nickel oxide was mixed alternatively with gamma-alumina, kaolinite, and hematite. These tailoring precursors are commonly used to prepare construction ceramics in the build...

The work was aimed at the investigation of kinetics Spark Plasma Sintering (SPS) α-Al2O3 particles with amorphous surface layers and effect on grain growth mechanical properties alumina. objects investigations comprised:(i) submicron powder, (ii) powder particles' surfaces, (iii) fine-grained powder. powders (i) were used to analyze sintering kinetics. Powders initial particle sizes shrinkage t...

• Temperature-dependent radiative properties of ceramic powders up to 1000 °C. Diffuse reflectance measurements (1–20 µm) above temperature limit background. Sintered bauxite (ACCUCAST) evaluated for concentrated solar power applications. ACCUCAST correlates most strongly alumina and silica wavelengths > 5 µm. Thermal emittance larger than T ? 600 Radiative are critical quantify energy fluxes b...

Conventional flash sintering is difficult to adapt ceramics with a very low electrical conductivity like pure alumina. Alternatively, the latter can be heated by microwave/matter interaction due dielectric losses. Microwave energy also preferable as it allows rapid contactless and volumetric heating that initiated susceptors. This work presents assembly designed for this purpose using 2.45 GHz ...