High temperature properties of CrAlN, CrAlSiN and AlCrSiN coatings – structure and oxidation


Polcar, Tomas and Cavaleiro, Albano (2011) High temperature properties of CrAlN, CrAlSiN and AlCrSiN coatings – structure and oxidation. Materials Chemistry and Physics, 129, (1-2), 195-201. (doi:10.1016/j.matchemphys.2011.03.078).

Download

Full text not available from this repository.

Description/Abstract

CrAlN, CrAlSiN and AlCrSiN coatings were deposited by cathodic arc deposition technique from composite targets. Three targets were used: (i) Cr/Al ratio close to 1, (ii) Cr/Al ratio close to 1 with Si addition, and (iii) Cr/Al ratio close to 1/2 and Si addition. Nitrogen flow was kept constant during the depositions. The Cr/Al ratio of the films, measured by electron probe microanalysis (EPMA), was similar to that of the target and the silicon content was in the range 3–4 at.%. The coatings were deposited onto FeCrAl alloy and WC/Co mirror-polished substrates. To analyze the coating structure, X-ray photoelectron (XPS) and X-ray diffraction (XRD) analysis were used. The evolution of the coating structure up to 1000 °C was in situ measured in a XRD apparatus equipped with heating plate. The films oxidation behavior was characterized by thermogravimetric analysis (TGA) at two selected temperatures. The annealed coatings were analyzed by XRD and scanning electron microscopy with energy-dispersive X-ray spectroscopy (EDX). CrAlSiN showed low oxidation resistance being partially oxidized at 800 °C. Moreover, the film exhibited low thermal stability, since the cubic nitride phases transformed to hexagonal nitrides at relatively low temperatures. CrAlN oxidation behavior was more promising; nevertheless, AlCrSiN showed excellent thermal stability with cubic nitrides observed even after heating to 1300 °C. The oxidation of this film at 900 and 1000 °C was negligible.

Item Type: Article
ISSNs: 0254-0584 (print)
Keywords: thin films, oxidation, thermogravimetric analysis, arc discharges, diffusion
Subjects: Q Science > QC Physics
T Technology > TP Chemical technology
Divisions: Faculty of Engineering and the Environment > Engineering Sciences > n CATS Research Group
ePrint ID: 199855
Date Deposited: 20 Oct 2011 15:52
Last Modified: 27 Mar 2014 19:46
URI: http://eprints.soton.ac.uk/id/eprint/199855

Actions (login required)

View Item View Item