| AVS 55th International Symposium & Exhibition | |
| Advanced Surface Engineering | Wednesday Sessions |
| Session SE-WeM |
| Session: | Atmospheric Pressure Treatments and Hard and Nanocomposite Coatings |
| Presenter: | J. Patscheider, EMPA, Switzerland |
| Authors: | L. Castaldi, EMPA, Switzerland D. Kurapov, OC Oerlikon Balzers AG, Switzerland A. Reiter, OC Oerlikon Balzers AG, Switzerland V. Shklover, ETH Zurich, Switzerland J. Patscheider, EMPA, Switzerland |
| Correspondent: | Click to Email |
The influences of adding silicon and oxygen during deposition of CrN by reactive cathodic arc evaporation on composition, structure, hardness and thermal stability were investigated. Both Cr-N-X phase ternary systems, where X denotes O or Si, exhibit a strong influence of X on hardness and thermal stability. Addition of these two elements leads to a decrease of the grain size of the cubic Cr-N-X phase, at the composition of optimum performance, down to a third or fourth of that of undoped CrN. XRD investigations suggest at least a partial substitution of N by O accompanied by the formation of an amorphous phase at higher O content, thereby forming a nanocomposite structure. The hardness of Cr-N-O coatings increases with increasing the oxygen content up to a value of 28 GPa, while fully oxidized Cr2O3 films showed lower hardness values around 12 GPa. The addition of Si resulted in a maximum hardness of Cr-N-Si of about 25 GPa. Cr-N-X coatings showed both an onset of oxidation which was promoted by about 200°C as compared to that of CrN. The underlying mechanisms, as evidenced by the performed measurements, will be discussed.