Microstructural influence of the thermal behavior of arc deposited TiAlN coatings with high aluminum content
Journal article, 2021

The influence of the microstructure on the thermal behavior of cathodic arc deposited TiAlN coatings was studied as a function of isothermal annealing. Two compositionally similar but structurally different coatings were compared, a Ti0·34Al0·66N0.96 coating with a fine-grain structure consisting of a mixture of cubic (c) and hexagonal (h) phases, and a Ti0·40Al0·60N0.94 coating with a coarse-grain structure of cubic phase. By in situ wide-angle synchrotron x-ray scattering, spinodal decomposition was confirmed in both coatings. The increased amount of internal interfaces lowered the decomposition temperature by 50 °C for the dual-phase coating. During the subsequent isothermal anneal at 1000 °C, a transformation from c-AlN to h-AlN took place in both coatings. After 50 min of isothermal annealing, atom probe tomography detected small amounts of Al (∼2 at.%) in the c-TiN rich domains and small amounts of Ti (∼1 at.%) in the h-AlN rich domains of the coarse-grained single-phase Ti0·40Al0·60N0.94 coating. Similarly, at the same conditions, the fine-grained dual-phase Ti0·34Al0·66N0.96 coating exhibits a higher Al content (∼5 at.%) in the c-TiN rich domains and higher Ti content (∼15 at.%) in the h-AlN rich domains. The study shows that the thermal stability of TiAlN is affected by the microstructure and that it can be used to tune the reaction pathway of decomposition favorably.

Vapor deposition

Synchrotron radiation

Microstructure

Coating materials

Author

A. B.B. Chaar

Linköping University

Universität des Saarlandes

Lina Rogström

Linköping University

M. P. Johansson-Jöesaar

Seco Tools AB

Linköping University

J. Barrirero

Universität des Saarlandes

Linköping University

Hisham Aboulfadl

Universität des Saarlandes

Chalmers, Physics, Microstructure Physics

N. Schell

Helmholtz

D. Ostach

Helmholtz

Frank Mücklich

Universität des Saarlandes

M. Oden

Linköping University

Journal of Alloys and Compounds

0925-8388 (ISSN)

Vol. 854 157205

Subject Categories

Inorganic Chemistry

Manufacturing, Surface and Joining Technology

Materials Chemistry

DOI

10.1016/j.jallcom.2020.157205

More information

Latest update

12/2/2020