Microstructure, stress and mechanical properties of arc-evaporated Cr-C-N coatings
2001 (English)In: Thin Solid Films, ISSN 0040-6090, Vol. 385, no 1-2, 190-197 p.Article in journal (Refereed) Published
The relationships between coating microstructure and properties in the Cr-C-N system have been investigated as a function of composition and post-deposition annealing. Coatings of varying compositions were grown using arc-evaporation, by varying the reactive gas flow ratio fR = f(C2H4)/f(N2) from 0 to 0.2, and were found to consist primarily of the cubic d-Cr(C,N) phase. Changes in both the unstressed lattice parameter, ao, and X-ray diffraction background intensity indicate that both the carbon concentration within the d-phase and amorphous/crystalline content increases with fR. Increasing fR also decreases the magnitude of the compressive biaxial residual stress, from approximately 6 to 1 GPa, while increasing both the inhomogeneous stress and thermal stability. The elastic modulus and hardness of as-deposited coatings were determined from nanoindentation to be 320 and 23 GPa, respectively, for moderate carbon concentrations (fR=0.05). Concurrent variations in microstructure and hardness with post-deposition annealing indicate that the as-deposited hardness is significantly enhanced by the microstructure, primarily by lattice defects and related stresses (microstresses) rather than average stresses (macrostresses).
Place, publisher, year, edition, pages
2001. Vol. 385, no 1-2, 190-197 p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-30190DOI: 10.1016/S0040-6090(01)00759-3Local ID: 15681OAI: oai:DiVA.org:liu-30190DiVA: diva2:251012