Aluminum-rich HPPMS (Cr1-xAlx)N coatings deposited with different target compositions and at various pulse lengths

Target properties and pulse configuration are important factors in high power pulsed magnetron sputtering. The present work deals with analyses of the effects of the pulse length, i.e., duty cycle on the HPPMS process and on the properties of Al-rich (Cr1-xAlx)N coatings deposited with plugged targets in an industrial scale unit. The results showed that the peak power density increased from 0.32 kW/cm(2) to 0.86 kW/cm(2) as the pulse length decreased from t(on) = 200 mu s to 40 mu s. (Cr1-xAlx)N coatings with a high aluminum content between x = 68 at% and x = 76 at% were produced. The deposition rate reveals a constant behavior using different Al-rich targets at the same pulse length. A mixture of cubic and hexagonal (Cr1-xAlx)N phases was found for each coating. Furthermore, a finer and denser morphology as well as a smoother surface were observed at reduced pulse length compared to large pulse configuration due to the high peak current and power density. The maximum hardness of H-U = 30.0 GPa and a moderate elastic modulus of Err = 421 GPa were achieved for the (Cr0.30Al0.70)N coating deposited at a pulse length of t(on) = 40 mu s, i.e., duty cycle of 2%. (C) 2015 Elsevier Ltd. All rights reserved.