| AVS 61st International Symposium & Exhibition | |
| Advanced Surface Engineering | Tuesday Sessions |
| Session SE+NS+TR-TuM |
| Session: | Nanostructured Thin Films and Coatings |
| Presenter: | Jianliang Lin, Southwest Research Institute |
| Authors: | J. Lin, Southwest Research Institute R. Wei, Southwest Research Institute K. Coulter, Southwest Research Institute C. Bitsis, Southwest Research Institute P.M. Lee, Southwest Research Institute |
| Correspondent: | Click to Email |
Hard and thick (15-20 µm) TiSiCN nanocomposite coatings have been developed to improve the wear resistance and reduce the overall average friction for diesel engine piston rings. The coatings were deposited by sputtering Ti metal targets in a reactive atmosphere using a plasma enhanced magnetron sputtering (PEMS) process. The reactive mixture contains argon, nitrogen, acetylene gases, and hexamethyldisilazane vapor which were introduced into the chamber using a liquid evaporation/delivery system. The substrates were AISI 304 stainless steel coupons and piston rings. The TiSiCN coatings with different elemental compositions and microstructures were prepared by varying the hexamethyldisilazane and acetylene gas/vapor concentrations and the target power. The microstructure of the coatings was characterized using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. The adhesion strength and mechanical and tribological properties of the coatings were measured using HRC tests, nanoindentation and ball-on-disk wear tests. By optimizing the composition and microstructure of the coatings, thick TiSiCN nanocomposite coatings with excellent adhesion and a dry sliding friction less than 0.2 have been obtained. The optimized coating systems were applied on the piston rings, which were evaluated on a Plint TE77 reciprocating bench rig and in the real diesel engine test. The principle for the increased wear resistance and the potential applications will be discussed in the paper.