Effects of Pulsed Bias Voltage on Microstructure and Properties of TiZrN/TiN Nano-Multilayer Films

Abstract:

TiZrN/TiN nano-multilayer films were deposited by hybrid method of arc ion plating and high-power impulse magnetron sputtering techniques on M2 high-speed steel and single crystal silicon substrates. The microstructure, element composition, phase structure, adhesion strength between the film and substrate, nanohardness, friction and wear properties and corrosion resistance of TiZrN/TiN nano-multilayer films were investigated. Results show that with the increase in pulsed bias voltage, the surface roughness of TiZrN/TiN nano-multilayer films is decreased to 0.345 μm when the pulsed bias voltage is –500 V, and the thickness of the films exhibits a fluctuant trend. The preferred orientation of TiZrN/TiN nano-multilayer films shifts from (111) crystal plane to (220) crystal plane. At a pulsed bias voltage of –200 V, the adhesion strength level between TiZrN/TiN nano-multilayer films and substrate reaches to HF2. The nanohardness and elastic modulus of the TiZrN/TiN nano-multilayer film are increased to 47.02 GPa and 382.28 GPa, respectively. The hardness is 5.2 times higher than that of M2 high-speed steel substrate (about 9 GPa). At the pulsed bias voltage of –200 V, the wear rate reaches 4.38×10^-8 mm³·N^-1·mm^-1, which indicates that the TiZrN/TiN nano-multilayer films have good wear resistance. The electrochemical corrosion test shows that the self-corrosion current density of TiZrN/TiN nano-multilayer films reaches the minimum value of 0.566 μA/cm², which is approximately 1/17 of that of the high-speed substrate (9.654 μA/cm²), and the film exhibits the slowest corrosion rate. Using the hybrid method of arc ion plating and high-power impulse magnetron sputtering can reduce the surface roughness of TiZrN/TiN nano-multilayer films. With the increase in pulsed bias voltage, the ion energy can be changed, which significantly enhances the hardness, wear resistance, and corrosion resistance of TiZrN/TiN nano-multilayer films compared with those of the M2 high-speed steel substrate.