Properties of Titanium Nitride Film Coated on Stainless Steel 304

Abstract

The characteristics of titanium nitride (TiN) film coated on the stainless steel substrates were studied under various processing conditions, e.g., different nitrogen flow rates and substrate temperatures. The TiN film was produced by reactive magnetron sputtering process under mixed gases pressure of argon and nitrogen with the stainless steel 304 substrates. X-ray diffraction was used to verify the TiN crystalline structure. The diffraction patterns of Ti₂N(101) and TiN (111)phase at 2θ =34.50° and 36.10°, respectively,were found when the nitrogen flow rate was 3.338 sccm.The nitrogen flow rates of 3.84 and 7.80 sccm only the TiN (111) peak was observed at 2θ = 36.10°. Scanning electron microscopy examination indicated that the film structure was more uniform and denser for higher substrate temperature. At 250°C, the film structure was nonuniform, there were some grooves and a big hump on titanium nitride film. Hardness measurements were performed by Nano Inderter to determine the mechanical properties of the films. A color of film was measured by spectrophotometer. TiN films have a uniform golden color. The result showed that the surface hardness of stainless steel which was coated with this film was higher. The film hardness at 50 nanometer depth was higher than that at 100 nanometer for films thickness of about 1 micron. The experiment result showed the highest hardness was obtained
when nitrogen flow rate was 7.80 sccm and titanium nitride film was TiN-phase.