Nitride based thin films for internal combustion engine pistons

Thin film technologies have developed with extreme rapidity in the last two decades either in terms of implementation or of industrial applications. In mechanical industry, the objectives of thin film coatings are mainly to improve the corrosion or the wear resistance, to reduce the coefficient of friction, to modify the surface microstructure, to improve the ability to retain lubricants and to optimize the lubrication of the mating surfaces.In internal combustion engines, the current trend is to save energy, that is to say, the reduction of fuel consumption for equal or higher power levels. To do so, it is necessary to reduce friction losses between surfaces in contact and increase their durability.In this book, we propose to apply tribological thin films on piston skirts and piston crown surfaces in order to increase the surface hardness and its corrosion resistance and to reduce the coefficient of friction. Particularly we present results on the effect of tungsten-titanium nitride based hard films.