Structure, deformation and fracture of arc evaporated Zr-Si-N ternary hard films
2014 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 258, 1100-1107 p.Article in journal (Refereed) Published
Zr-Si-N films with varying Si contents were grown on WC-Co substrates with an industrial scale reactive cathodic arc deposition technique. The microstructural changes correlate to variation in mechanical properties with different deformation mechanisms dominating for different structures. Si forms a substitutional solid solution in the cubic ZrN lattice up to 1.8 at. % in a fine columnar structure. Further Si additions results in precipitation of an amorphous (a)-SiNX phase and evolution of a nanocomposite structure (nc ZrN-a SiNX) which has completely suppressed the columnar structure at 6.3 at. % Si. The rotation-induced artificial layering during film growth was used as a marker to visualize the deformation of the film. A dislocation-based homogeneous plastic deformation mechanism dominates the columnar structure, while grain boundary sliding is the active mechanism mediating heterogeneous plastic deformation in the nanocomposite structure. Film hardness increases with increasing Si content in the columnar structure due to an effective solid solution strengthening. The deformation mechanism of localized grain boundary sliding in the nanocomposite structure results in lower hardness. When cracking is induced by indentation, the fine columnar structure exhibits pronounced crack deflection that results in higher fracture resistance compared to the nanocomposite films.
Place, publisher, year, edition, pages
Elsevier, 2014. Vol. 258, 1100-1107 p.
IdentifiersURN: urn:nbn:se:liu:diva-106760DOI: 10.1016/j.surfcoat.2014.07.024ISI: 000346895000134OAI: oai:DiVA.org:liu-106760DiVA: diva2:718614