As many transportation industries; one of the main levers of automotive industry to reduce CO2 emissions is mass and friction reduction. One way of achieving these objectives is using efficient coatings tailored for high tribological performances; to be applied in some heavily loaded engine parts. The aim of the present work was to develop metalceramic- lubricant composite coatings onto steel parts; which could exhibit the best compromise between several properties; primarily wear and seizure resistance; fatigue resistance and thermal resistance. For this; metal-based coatings with addition of hard particles and solid lubricants were produced using cold spray. The relations between the resulting multi-material coating microstructure and its tribological properties were studied. To meet high tribological properties; the interfaces between the different components were optimized by selecting carefully feed-stock powders and by testing a large range of process parameters. Alumina-reinforced bronze-based composite coatings were produced using powders with different morphologies. Aggregated ceramic powders revealed to be more beneficial for wear properties compared to massive powders. Graphite was also added in order to reduce seizure.

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