Influence of Substrate Negative Bias on Structure and Properties of TiN Coatings Prepared by Hybrid HIPIMS Method

TiN coatings were deposited using a hybrid home-made high power impulse magnetron sputtering (HIPIMS) technique at room temperature. The effects of substrate negative bias voltage on the deposition rate, composition, crystal structure, surface morphology, microstructure and mechanical properties were investigated. The results revealed that with the increase in bias voltage from −50 to −400 V, TiN coatings exhibited a trend of densification and the crystal structure gradually evolved from (111) orientation to (200) orientation. The growth rate decreased from about 12.2 nm to 7.8 nm per minute with the coating densification. When the bias voltage was −300 V, the minimum surface roughness value of 10.1 nm was obtained, and the hardness and Young's modulus of TiN coatings reached the maximum value of 17.4 GPa and 263.8 GPa, respectively. Meanwhile, the highest adhesion of 59 N was obtained between coating and substrate.