The nature of the interfacial bond has a major effect on degree toughening that can be achieved in ductile‐particle‐reinforced ceramic‐matrix composite. variation oxygen partial pressure during fabrication bonding an alumina‐nickel composite been investigated. Calculations suggest wetting alumina by nickel should always accompanied spinel (NiAl 2 O 4 formation. A range microstructures within single specimen have produced, however, indicating occurs more rapidly than formation and reduction...

The Knoop and Vickers indentation behaviour of spark plasma sintered SiC–5 wt.% B4C, B4C SiC–2.5 AlN–3 C armour ceramics have been investigated observations correlated with ballistic performance. Surface sub-surface indentation-induced damage has characterised via cross-sectioning serial ceramographic polishing techniques. nature the appears to be less influential than hardness in relation performance, but variability correlate Examination size effect curves shows that both predicted...

Surface treatments of silicon carbide have been investigated with the aim improving strength bond between ceramic and an epoxy adhesive. Three surface conditions characterised; as-fired, air re-fired KrF laser processed. A number characterisation techniques used to determine morphological chemical changes that occurred surface. Scanning electron microscopy processed samples showed surfaces appeared glassy, showing a different morphology. X-ray photoelectron spectroscopy indicated both had...

Glass‐ceramics are widely utilized in the electronics industry to provide electrical insulation and form leak‐tight joints with a range of metals. The coefficient thermal expansion ( CTE ) glass‐ceramic can be controlled by extent crystallization reduce detrimental tensile stresses joint. In recent years, there has been interest using titanium alloys, place stainless steels, due their lower density superior specific strength. this study, heat treatment strontium boroaluminate glass tailored...

Summary Composites consisting of an alumina matrix and 20 vol.% transition metal (Ni or Fe) particles, prepared by hot pressing powder blends, have been studied using spatially resolved transmission electron energy‐loss spectroscopy (EELS), and, to a lesser extent, high‐resolution microscopy (HREM). Particular attention was paid the elucidation chemical bonding mechanisms at metal‐ceramic interface; EELS spectra from interfacial regions being obtained via spatial difference technique. From...

The master sintering curve approach represents densification data in terms of a variable that combines time and temperature. Recently, finite‐element scheme to predict deformation requires only the instead full constitutive law as input has been developed. Here, modification original approach, so it is more suitable for analysis, presented. Finite‐element shape functions are used represent well curve. This confers extra flexibility even when not with analysis. For example, by using...

Nickel oxide (NiO) was screen printed onto the surfaces of 3 and 8 mol% yttria‐stabilized zirconia (YSZ) dense pre‐fired substrates then heat treated at temperatures from 1350° to 1550°C. The effect NiO dependent on yttria content substrate. In YSZ, it found alter phase composition predominantly tetragonal with a small amount cubic one consisting approximately equal amounts monoclinic phase. grains were much larger than ones contained more nickel. Furthermore, nickel observed migrate through...

The nuclear industry has used hard chromium plate for many years but is seeking alternatives, due to the adverse health effects of Cr(VI) employed in electroplating. In this study, testing and analysis regimes comparison sliding wear performance candidate materials have been established WC-(W,Cr)2C-Ni compared with that plate. was applied Inconel 625 substrates using a detonation gun thermal spray technique. Sliding performed ball-on-flat configuration reciprocating tribometer at 20 °C three...

The purpose of the study is to accelerate development ceramic materials for armour applications by substantially increasing information obtained from a high-energy projectile impact event. This has been achieved modifying an existing test configuration incorporate block ballistic gel, attached strike face system, capture fragments generated during event such that their final positions are maintained. Three different materials, representative major classes ceramics applications, alumina,...

This work provides new insight and evidence that challenges extends the accepted view of oxidation behaviour Kovar (ASTM-15). Specimens 2 mm diameter wire were oxidised in air at 700 or 800 °C for 10 min. The resulting oxide layers analysed by X-ray diffraction, photoelectron spectroscopy, scanning electron microscopy with energy-dispersive transmission Raman spectroscopy. Oxide approximately 4 µm thickness formed °C, respectively. These found to contain iron, cobalt traces nickel....

Hard chromium plate (HCP) has been the wear resistant coating of choice in nuclear industry for decades, but new protective coatings are required as a result hazardous nature Cr(VI) compounds used electroplating. This study compares performance candidate replacements materials, Cr2O3 and Cr3C2–NiCr. These two also compared with HCP WC-(W,Cr)2C–Ni assessed an earlier publication. The Cr3C2–NiCr were supplied having applied to Inconel 625 substrates using high velocity oxy fuel (HVOF) thermal...