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The effect of corrosion damage on cemented carbides was investigated. The study included residual strength assessment and detailed fractographic inspection of corroded specimens as well as detailed 3D FIB-FESEM tomography characterisation. Experimental results point out a strong strength decrease associated with localised corrosion damage, i.e. corrosion pits acting as stress raisers, concentrated in the binder phase. These pits exhibit a variable and partial interconnectivity, as a function of depth from the surface, and are the result of heterogeneous dissolution of the metallic phase, specifically at the corrosion front. However, as corrosion advances the ratio between pit depth and thickness of damaged layer decreases. Thus, stress concentration effect ascribed to corrosion pits gets geometrically lessened, damage becomes effectively homogenised and relatively changes in residual strength as exposure time gets longer are found to be less pronounced.

Linear intercept on scanning electron microscopy micrographs is the most commonly used measurement method to determine carbide grain size and contiguity in WC-Co cemented carbides (hardmetals). However, it involves manual time-consuming measurements and is critically dependent on the quality of the micrographs as well as on the identification and definition of grain boundaries. In this study a two-stage methodology for microstructural characterization of hardmetals is presented.

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The potential for the use of microwave radiation as an alternative energy source for the sintering and annealing of bulk, ceramic high- YBCO superconductors has been investigated with a view to taking advantage of the opportunities presented by this novel heating technique. Microwave heating has been found to offer the possibility of sintering `from the inside out' due to the nature of the temperature profile developed. As a result, ceramic YBCO bodies measuring 35 mm in diameter by 5 mm thick have been produced with completely uniform and high oxygen content (x = 7 in ) and densities up to 98% of theoretical. These properties were achieved using total processing times approximately one sixth of those required conventionally. A model for the microwave heating process is proposed.