Tribocorrosion of stellite 6 in sulphuric acid was studied with a pin-on-disc tribometer through test conditions of intermittent friction. The occurrence of a mechanism involving mechanical depassivation during friction and further repassivation during the latency period between two successive friction steps was demonstrated. Polarization curves measurements and wear measurements by weight loss together with microtopography surveys of the wear track

The combined corrosion-wear degradation of nano-structured Ni–SiC coatings in sliding contacts immersed in electrically conductive solutions is investigated in situ by electrochemical techniques (open-circuit potential measurements, EOC, the potentiodynamic polarization measurements, PD, and the electrochemical impedance spectroscopy). The coating thickness was 50 μm, with an average volume of dispersed phases inside nickel of 20%. The samples