The effects of copper addition on phase composition in (CrFeCo)1-yNy multicomponent thin films

• Published in: Applied surface science 2022-01, Vol.572, p.151315, Article 151315
• Main Authors: Rao, Smita G., Shu, Rui, Boyd, Robert, Febvrier, Arnaud le, Eklund, Per
• Format: Article
• Language: English
• Subjects: Coating; High entropy alloy; Magnetron sputtering; Multicomponent
• ISSN: 0169-4332; 1873-5584; 1873-5584
• DOI: 10.1016/j.apsusc.2021.151315

[Display omitted] •Multicomponent (CrFeCoCux)1-yNy=0.19 coatings deposited by reactive magnetron sputtering.•Effect of copper addition on structure, morphology and composition of low nitrogen containing thin films studied.•Cu induces stabilization of bcc. The Cantor alloy CrFeCoMnNi is generally fcc structured, but moderate changes in the composition can have a large influence on the phase formation. The aim of this study was to understand the changes brought on in low-nitrogen-containing (CrFeCo)1-yNy thin films with y = 0.19 on the addition of copper, an interesting metal in terms of atomic size and nitride formation enthalpy. (CrFeCoCux)1-yNy films were grown by reactive magnetron sputtering. The amount of copper in the films was increased from x = 0 to x = 0.15 to study competitive phase formation. Without Cu, two-phase fcc + bcc films were obtained. The addition of Cu was found to stabilize the bcc structure despite the fact that Cu as a pure metal is fcc. Nanoindentation tests showed slight increase in hardness with initial Cu addition from 11 GPa to 13.7 ± 0.2 GPa. The occurrence of pile up as opposed to cracking is an indication of the film’s ductility.