To withstand oxidation at a temperature ≥ 850 °C, an optimized Ti1−xAlxN coating was grown via reactive High Power Impulse Magnetron Sputtering (HiPIMS) technology on three identical Ti0.48Al0.48Cr0.02Nb0.02 billets. Different substrate surface pre-treatments were designed to increase performance: i) mechanical polishing, ii) mechanical polishing combined with a strong plasma etching, and iii) mechanical polishing coupled to both a weak plasma etching and a Ti1−yAly metallic interlayer deposition. Then, all the specimens were cyclically heat treated up to 200 cycles at 950 °C, using a Burner Rig (BR) facility. The chosen Ti1−xAlxN/substrate interface architecture considerably influenced average compressive residual stress (Sres) and adhesion of just deposited films. Moreover, it was possible to identify a clear relationship between Sres behavior and each coating comportment after BR tests. It became clear that the weak plasma etching/Ti1−yAly interlayer match helped improving the system stability (i.e. very low average residual stress thermal relaxation) thus guarantying high temperature oxidation resistance.
Deambrosis, S.M., Montagner, F., Zin, V., Fabrizio, M., Badini, C., Padovano, E., et al. (2018). Ti1−xAlxN coatings by Reactive High Power Impulse Magnetron Sputtering: film/substrate interface effect on residual stress and high temperature oxidation. SURFACE & COATINGS TECHNOLOGY, 354, 56-65 [10.1016/j.surfcoat.2018.09.004].