AVS 54th International Symposium | |
Advanced Surface Engineering | Monday Sessions |
Session SE-MoM |
Session: | Hard and Nanocomposite Coatings: Synthesis, Structure, and Properties |
Presenter: | J.E. Klemberg-Sapieha, Ecole Polytechnique, Canada |
Authors: | M. Benkahoul, Ecole Polytechnique, Canada P. Robin, Ecole Polytechnique, Canada L. Martinu, Ecole Polytechnique, Canada J.E. Klemberg-Sapieha, Ecole Polytechnique, Canada |
Correspondent: | Click to Email |
Cr-Si-N thin films were deposited by pulsed DC reactive dual magnetron sputtering with different concentrations of Si. Microstructural evolution and mechanical properties of these thin films were studied using XRD and nanoindentation measurements. Three regions of different Si concentration [Si] were distinguished: For [Si] < 2.3 at.%, the grain size (D) doesn’t significantly change with increasing [Si]. For 2.3 < [Si] <7 at.%, D decreases as [Si] increases. At higher [Si], a relatively rapid decrease of D is observed with increasing [Si]. Nanohardness (H) behaviour of these thin films as a function of [Si] is comparable to that observed in the Me-Si-N (Me: Ti, Nb, Zr,…) nanocomposite materials. For [Si] ~2.3 at.%, H is 24 GPa, H3/Er2 ~ 0.24 GPa, and the elastic recovery, We ~ 60%, is comparable with CrN, for which H ~ 18 GPa, H3/Er2 ~ 0.1 GPa, and We ~ 35%. Based on the evolution of the microstructure of these films, solid solution hardening is proposed as the main mechanism to explain the changes observed for [Si] < 2.3 at.% in the Cr-Si-N films, rather than the nanocomposite structure. Subsequently, we systematically studied the deposition of Cr-Si-N films on SS410 steel using a duplex treatment consisting of surface nitriding and deposition of a Cr bond coat. The influence of [Si] on the tribological properties of the Cr-Si-N coatings was found to lead to a reduction of the wear coefficient by a factor of 100 compared to bare SS410 substrate.