Abstract: Arc ion plating method was used to deposit TiSiN films on M2 high-speed steel(M2 HSS) and Si wafer substrates by changing the pulsed bias duty ratio. Effect of pulsed bias duty ratio on morphology, element composition, phase structure, nano-hardness and corrosion resistance of the TiSiN films was studied. The results show that when the pulsed bias duty ratio is 30%, the number of macroparticles on the surface of the TiSiN film reaches a maximum of 832, and when the duty ratio is 60%, the number of macroparticles decreases to 451. With the increases of pulsed bias duty ratio from 20% to 50%, the film thickness on the surface of the Si specimen increases from 390.8 nm to 2.339 μm. When the duty ratio is 30%, the content of Si element in the film is up to 13.88at%, the (220) crystal plane is the preferred orientation, the grain size reaches the minimum value of 5.05 nm, the hardness reaches 28.34 GPa, and the self-corrosion current density reaches the minimum value of 0.5306 μA/cm². When the duty ratio is 40%, the (111) crystal plane is the preferred orientation, the content of Si element is reduced to the minimum value of 0.46at%. When the duty ratio is 50%, the grain size of the (111) crystal plane reaches 13.22 nm, the hardness reaches the maximum value of 42.08 GPa, and the self-corrosion potential reaches the maximum value of -0.324 V (vs SCE). When the duty ratio is more than 40%, the number of macroparticle defects and the Si content in the TiSiN film are reduced. Meanwhile the preferred orientation of grain growth of the TiSiN film changes from (220) to (111), and the hardness and corrosion resistance of the TiSiN films are improved.

Key words: arc ion plating, TiSiN film, duty ratio, nano-hardness, corrosion resistance