Tribological studies of DLC coating for Piston Rings

The development of this work arose as a preparation for a future project of CEMMPRE that consists in the production of DLC thin films for piston rings of high compression internal combustion engines deposited by HiPIMS in DOMS mode. The objective of this work is to study the influence of certain deposition parameters in the samples, in order to obtain a guideline to follow in the project. Variation in substrate bias shows that by increasing substrate bias in deposition process hardness of DLC coatings increases. By increasing substrate bias, Carbon ions in plasma are attracted with more momentum toward substrate and results in more compact structure of films. As a part of this thesis, Ne is produced in to discharge gas and effects of Ne are studied. Ne increases the degree of Carbon ionization in the plasma so it increases the sp3 ratio in the structure of the film. Since sp3 is more powerful hybridization, coatings that are deposited with Ne show more hardness in Nano indentation test.