Pulsed electrode surfacing (PES) is a microwelding surfacing process for the successful deposition of ultrahard wear and erosion resistant ceramic coatings on metals. The present study investigates titanium diboride deposition on oxygen free high conductivity Cu. A thin and irregular coating with cracks was obtained on the Cu substrate, with the ceramic/metal interface distinct in TiB2 deposited on Cu leading to decohesion at the interface. The present work has been compared with an earlier study on TiB2 coatings deposited on 1018 steel using the PES technique. The difference in nature of the interfaces has been related to wettability, and the role of copper and iron as binders for TiB2 ceramics has been addressed. Iron acts as an excellent binder for TiB2, providing a crack free coating and a strong interface, whereas Cu is a poor binder, leading to a weak ceramic/metal interface.

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Barium titanate ceramic thin films fabricated by the electrophoretic deposition technique were recrystallised using scanned CO2 laser irradiation. Conventionally the film is sintered at high temperature (1200°C) to increase adhesive forces between powdered ceramic film and substrate. During this process, however, many micropores and microcracks are produced owing to large shrinkage of fine aggregate grains in the film layer. In order to produce preferred orientation grainswithout these defects, the films were instantaneously melted by laser irradiation and recrystallised. The microstructure of the resulting thin film showed significant growth of platelike crystals and strip grain morphology on the surface. The recrystallised phase of BaTiO3 was tetragonal. Thus the laser scanning process appears to be suited to generating large grains with preferred orientation. In hysteresis D–E curve measurements, remanent polarisation of 48 mCm –2 and coercive field of 320 kVm–1 were the best dielectric and ferroelectric properties obtained in a film of 4 μm thickness.

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