Influence of Ag additions on the structure, mechanical properties and oxidation behaviour of CrAlNAg coatings deposited by sputtering

In this work, the influence of Ag additions into CrAlN coatings on surface morphology, chemical composition, structure, hardness and oxidation behaviour was studied. Increasing content decreased size morphological features produced a more compact coatings. All displayed fcc structure typical transition metal nitrides; silver phase indexed for with concentration ≥8.6 at.%. XPS results confirmed that existed as nanoclusters within coating structure. A maximum around 23 GPa observed 8.6 at.% Ag. The decrease further increase in ascribed to much softer character phase. reference best resistance lowest onset point oxidation. good attributed formation continuous protective thin Cr2O3 layer top oxide layer. degraded coatings, since diffusion scale created extra paths ions Cr-O AgCrO2 CrAlNAg9 coating, particular temperature at 800 °C, responsible low compared same oxidized 900 °C.