Nitrogen-doped bcc-Cr films: Combining ceramic hardness with metallic toughness and conductivity. (September 2016)

• Record Type: Journal Article
• Authors: Greczynski, G.; Lu, J.; Tengstrand, O.; Petrov, I.; Greene, J.E.; Hultman, L.
• Is Part Of: Scripta materialia. Volume 122(2016)
• Page Start: 40
• Page End: 44
• Publication Date: 2016-09
• Subjects: CrN -- Thin films -- Toughness -- Resistivity -- Magnetron sputtering -- HIPIMS -- Transition-metal nitrides -- Ion mass spectrometry; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2016.05.011
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: We report the first results on nanostructured N-doped bcc -Cr films exhibiting the unique combination of ceramic hardness with metallic toughness and electrical conductivity at unexpectedly low N concentrations, ~ 5 at.%. The Cr:N films are deposited at 200 °C in N2 /Ar mixtures by high-power pulsed magnetron sputtering using tunable time-domain control of Cr + and Cr 2+ ion fluxes incident at the film growth surface. Subplanted N atoms impede annealing of metal-ion induced point defects and hinder bcc -Cr grain growth, resulting in a material with a nearly isotropic nanostructure and atomically smooth surface, rather than typical Cr:N solid solutions consisting of faceted microcolumns. Graphical abstract: