Investigation on the structure and properties of AlxCr1−xN coatings deposited by reactive magnetron co-sputtering

Al-rich AlxCr1−xN coatings have been deposited by reactive magnetron co-sputtering using a direct current (DC) power source to Al and a radio frequency (RF) power source to Cr target. The crystal structure, chemical composition, surface morphology, thickness and hardness of the AlxCr1−xN coatings which were prepared at various N2 flow rates and working pressures have been systemically investigated. The results show a strong effect of N2 flow rates and working pressures on the phase composition and microstructure as well as the Al content in AlxCr1−xN coatings. The present results also show Al contents play an important role in the hardness of the AlxCr1−xN coatings, which demonstrates the highest hardness for Al contents close to the maximum solubility in cubic AlxCr1−xN.