Matériaux&Techniques Mechanical properties of PVD Al1−xCrxN thin

AlCrN; PVD thin film; nano-indentation; sin2 ψ method Abstract – Al1−xCrxN thin films have been sputter deposited using either ion-beam (IBS) or magnetron. The structure, mechanical properties and residual stress state have been investigated using X-Ray diffraction, curvature measurements and nano-indentation. The presence of a 〈200 〉 fiber texture associated with compressive global stresses was evidenced in the studied 0.6–0.85 Cr at. % range with the largest level for IBS. In-grain stresses were determined to be compressive for IBS while tension was found in the case of magnetron sputtering. The obtained stress-free lattice parameters a0 revealed difference between the processes, IBS being more energetic. The in-grain residual stress values of IBS samples are twice as large as those obtained using curvature method; this might be due to 〈200 〉 texture effects and/or an over estimate of the elastic moduli. Hardness of the films was obtained in a range extending from 16 to 27 GPa correlated to residual stress level when compared to literature. Mots-clés: AlCrN; film mince PVD; nano-indentation; méthode des sin2