TY - THES

T1 - Influence of Fe impurities on structure and properties of AlCrN films grown by cathodic arc evaporation

AU - Mühlbacher, Marlene

N1 - embargoed until 16-11-2016

PY - 2011

Y1 - 2011

N2 - The influence of Fe impurities with contents of up to 2 at.% in AlCr targets on the properties of arc-evaporated AlCr(Fe)N coatings was investigated. Analyses of the synthesised coatings by electron microscopy and X-ray diffraction reveal no significant changes in the microstructure. The incorporated Fe atoms are homogeneously distributed and substitute Cr and Al atoms in the crystal lattice as suggested by elemental mappings and X-ray photoelectron spectroscopy. No pronounced modification of the mechanical properties is evident. However, thermogravimetric analysis in oxygen containing atmosphere reveals a lower oxidation onset temperature for the coatings with incorporated Fe. A chemical analysis of oxidised coatings by Raman spectroscopy discloses the formation of Cr2O3 at 800 to 900°C if Fe is present in the coating. This lower oxidation onset results in a slightly reduced wear resistance at temperatures up to 700°C. In contrast, the presence of Fe delays the oxidation reaction at temperatures exceeding 1000°C, presumably due to the formation of a dense oxide scale protecting the coating from further oxidation.

AB - The influence of Fe impurities with contents of up to 2 at.% in AlCr targets on the properties of arc-evaporated AlCr(Fe)N coatings was investigated. Analyses of the synthesised coatings by electron microscopy and X-ray diffraction reveal no significant changes in the microstructure. The incorporated Fe atoms are homogeneously distributed and substitute Cr and Al atoms in the crystal lattice as suggested by elemental mappings and X-ray photoelectron spectroscopy. No pronounced modification of the mechanical properties is evident. However, thermogravimetric analysis in oxygen containing atmosphere reveals a lower oxidation onset temperature for the coatings with incorporated Fe. A chemical analysis of oxidised coatings by Raman spectroscopy discloses the formation of Cr2O3 at 800 to 900°C if Fe is present in the coating. This lower oxidation onset results in a slightly reduced wear resistance at temperatures up to 700°C. In contrast, the presence of Fe delays the oxidation reaction at temperatures exceeding 1000°C, presumably due to the formation of a dense oxide scale protecting the coating from further oxidation.

KW - AlCrN

KW - CrAlN

KW - Fe-Verunreinigungen

KW - kathodische Lichtbogenverdampfung

KW - Hartstoffschichten

KW - physikalische Gasphasenabscheidung

KW - AlCrN

KW - CrAlN

KW - Fe impurities

KW - cathodic arc evaporation

KW - hard coatings

KW - physical vapour deposition

M3 - Diploma Thesis

ER -