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Cu/graphite composites with 30 and 50 vol.% of graphite were prepared. Copper coated graphite particles enabled to prepare more homogeneous structure at 50 vol.% of graphite as simple powder mixture. In the case of 30 vol.% of graphite, composite prepared from mixture of coated graphite and copper powders is more heterogeneous as simple powder mixture. Measured CTE of coated composites was significantly smaller at both compositions. It is the result of the different area of copper-graphite interface that is established only by mechanical clamping. For coated composites the area of interface increases significantly due to avoiding graphite clustering. Simple model was proposed to predict this behaviour on the basis of anisotropy of graphite CTE. Further, the model can be used for calculation of the thermal expansion coefficient of the graphite reinforcement. K e y w o r d s : metal matrix composites, thermal expansion, coating

<p class="AMSmaintext">The electro spark deposition (ESD) method was used to create hard wear resistant layers of TiB₂ ceramic onto Ti6Al4V titanium alloy. Various deposition parameters and ways and condition of deposition were employed in this study. It was showed that the TiB₂ layer on Ti6Al4Vcan be successfully created even using hand operating ESD equipment. Then, the microstructures of the obtained layers TiB₂ layer on Ti6Al4Vwere investigated using scanning electron microscope. Finally optimal conditions of the electro spark deposition were determined with respect to the obtained microstructure. It was also demonstrated that using of protective argon atmosphere is vital for creation of pore free TiB₂ ceramic layer on Ti6Al4V titanium alloy.</p>

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