The Effects Of Deposition Conditions On The Mechanical Properties Of Titanium Silicon Nitride Nanocomposite Coatings
Abstract
Titanium Silicon Nitride has received much attention in recent years for its theoretical super hardness and oxidation resistance at high temperature. In this work, the mechanical properties of TiSiN thin films including hardness, coefficient of friction, wear rate, wear mechanism were studied in detail using nanoindentation, pin-on-disk tribometer, optical profilometer, SEM and XPS. Four deposition conditions were varied to find the optimal conditions that produce the TiSiN film with the highest hardness and the best wear resistance. First, four substrate biases (100V, 200V, 300V, and 500V) were used, respectively. Then, different power (50W, 55W, 60W) and different N2 ratio (20%, 25%) were applied to Si target. Finally, three rotation speeds of the substrate holder (1RPM, 3RPM, and 6RPM) were utilized. Our study results demonstrated that TiSiN coating deposited at 100V bias, 60W Si power, 25%N2 gas mixture, and 6 RPM rotation speed has the highest hardness of 38.9GPa. High COFs of greater than 1.0 were observed in all films tested. Wear rates decreases as the hardness of the film decreases. The wear mechanism was assumed to be a three body wear due to the presence of counter material debris in the wear track.