Influence of substrate bias voltage on deposition behavior and micro-indentation hardness of Ti–Si–N coatings by a hybrid coating system of arc ion plating and sputtering techniques

In this work, the influence of substrate bias voltage on deposition behaviors such as deposition rate, film composition, macroparticles and surface roughness were investigated for the Ti–Si–N coatings deposited on WC–Co substrates by a hybrid coating system of arc ion plating and sputtering techniques. Also, the hardness and Youngʹs modulus of Ti–Si–N coatings by nanoindentation tests were investigated with the substrate bias voltage. Applying substrate bias voltage up to −100 V during Ti–Si–N deposition resulted in the significant diminution of macroparticles and smoothening of surface morphology. The micro-indentation hardness and Youngʹs modulus values were also significantly increased at a bias voltage of −100 V, and showed the highest values of ∼60 and ∼700 GPa, respectively. However, increasing the negative bias voltage above −100 V caused the continual reduction of those properties, and reduced both deposition rate and Si content in the Ti–Si–N coatings.