TY - JOUR

T1 - Oxidation resistance of cathodic arc evaporated Cr0.74Ta0.26N coatings

AU - Kainz, Christina

AU - Saringer, Christian

AU - Burtscher, Michael

AU - Tkadletz, Michael

AU - Stark, Andreas

AU - Schell, Norbert

AU - Pohler, Markus

AU - Czettl, Christoph

AU - Kiener, Daniel

AU - Schalk, Nina

N1 - Publisher Copyright: © 2021 The Author(s)

PY - 2022/4/1

Y1 - 2022/4/1

N2 - Owing to their combination of high hardness and increased fracture toughness, CrTaN coatings have recently gained increasing interest as suitable candidates for metal cutting applications. However, up to now, the detailed mechanisms underlying the oxidation of this promising coating system are not thoroughly understood. Thus within this work, the evolution of microstructure and phase composition of a cathodic arc evaporated Cr 0.74Ta 0.26N coating were illuminated in ambient atmosphere up to 1400 °C. In situ high-energy X-ray diffraction showed that powdered face-centered cubic (fcc) CrTaN displays an excellent oxidation resistance up to ∼1050 °C, where the formation of tetragonal (t) CrTaO 4 and rhombohedral (r) Cr 2O 3 sets in. The compact CrTaN deposited on sapphire subjected to 1225 °C in ambient atmosphere exhibits intact fcc-CrTaN regions near the substrate, a porous intermediate layer of r-Cr 2O 3 and t-CrTaO 4 and a dense r-Cr 2O 3 oxide scale at the surface.

AB - Owing to their combination of high hardness and increased fracture toughness, CrTaN coatings have recently gained increasing interest as suitable candidates for metal cutting applications. However, up to now, the detailed mechanisms underlying the oxidation of this promising coating system are not thoroughly understood. Thus within this work, the evolution of microstructure and phase composition of a cathodic arc evaporated Cr 0.74Ta 0.26N coating were illuminated in ambient atmosphere up to 1400 °C. In situ high-energy X-ray diffraction showed that powdered face-centered cubic (fcc) CrTaN displays an excellent oxidation resistance up to ∼1050 °C, where the formation of tetragonal (t) CrTaO 4 and rhombohedral (r) Cr 2O 3 sets in. The compact CrTaN deposited on sapphire subjected to 1225 °C in ambient atmosphere exhibits intact fcc-CrTaN regions near the substrate, a porous intermediate layer of r-Cr 2O 3 and t-CrTaO 4 and a dense r-Cr 2O 3 oxide scale at the surface.

UR - http://www.scopus.com/inward/record.url?scp=85122515182&partnerID=8YFLogxK

U2 - 10.1016/j.scriptamat.2021.114492

DO - 10.1016/j.scriptamat.2021.114492

M3 - Article

VL - 211.2022

JO - Scripta materialia

JF - Scripta materialia

SN - 1359-6462

IS - 1 April

M1 - 114492

ER -