Wettability and interface microstructure were studied for Nb-containing melts in the contact with ceramic oxide materials of Al2O3-SiO2 system. Ni-40.5 at.%Nb and Au-(0-20) at.%Nb alloys were investigated as prospective alloys for high temperature brazes. Ceramic samples ranged in composition from pure Al2O3 to pure SiO2. The wettability was measured by the sessile drop method. Microstructure o...

The purpose of the present study is to evaluate the fracture load of composite-based repairs to fractured zirconium oxide (Z) crowns and to ceramic-fused-to-metal (CM) crowns, comparing different mechanical surface preparation methods. A total of 75 crowns were repaired; samples then underwent dynamic loading and thermocycling. Final fracture load values for failure of the repaired crowns were ...

We employ first-principles density functional calculations to explore atomic-level interactions and predict the ideal work of adhesion at the SiO2/nickel and ZrO2/SiO2 interfaces. We find that chemical bonding at the interface serves to strengthen significantly interfaces formed with SiO2, which exhibits significant covalent bonding character, relative to those formed using more ionic oxides, s...

The purpose of this study was to use a tape casting technique to develop an Al2O3 fiber-reinforced Al2O3-based ceramic material (Al2O3-fiber/Al2O3 composite) into a new type of dental ceramic. The Al2O3-based ceramic used a matrix consisting of 60 wt% Al2O3 powder and 40 wt% SiO2-B2O3 powder. The prepreg sheets of Al2O3-fiber/Al2O3 composite (in which uniaxially aligned Al2O3 fibers were infilt...

Nanocomposite high resistive soft magnetic materials Fe/SiO2 ~Fe volume fraction 50%! have been synthesized using a wet chemical reaction method. A series of metal-ceramic Fe/SiO2 nanocomposite powder samples were obtained by annealing the precursor at temperatures from 400 to 900 °C in the presence of a reducing agent. The compositions of the precursor and the successive heat-treated samples h...

Lithium aluminosilicate powder precursors of compositions Li2O:Al2O3:SiO2 as 1:1:2; and 1:1:3.11 were synthesized and sintered by the Spark Plasma Sintering technique. The sintering conditions were adjusted to obtain dense ceramic materials in an attempt to avoid the presence of a glassy phase. XRD and SEM images were employed for composition and microstructure characterization. The coefficient...

The effect of iron oxide content on the crystallisation of a diopside glass–ceramic glaze was investigated using a glass–ceramic frit in the K2O–ZnO–MgO–CaO–Al2O3–SiO2 system and a granite waste glass. Measurements by X-ray diffraction (XRD) combined with scanning electron microscopy (SEM) and EDX microanalysis showed that the distribution of Fe ions among different crystalline phases such as f...

BACKGROUND Bioactive glass-ceramics have the ability to directly bind to bones and have been widely used as bone graft substitutes due to their high osteoconductivity and biocompatibility. CaO-SiO2-P2O5-B2O3 glass-ceramics are known to have good osteoconductivity and are used as bone graft extenders. METHODS This study aimed to evaluate the effects of the resorbing properties of glass-ceramic...