Study on the Formation Mechanism of Surface Color of Oxide Film for Ti-6Al-4V in Cutting Process

The oxide film can be formed on the cutting surface of titanium alloy during cutting process, which affects the mechanics performance of titanium alloy. The single factor dry cutting experiment was carried out for the titanium alloy (Ti-6Al-4V) to investigate the formation mechanism of the color of oxide film. The oxide film consists of Anatase type TiO₂, Rutile type TiO₂ and Al₂O₃. The content of Al₂O₃ and rutile TiO₂ increases with increasing feed rate. The surface of oxide film appears different colors. The larger the feed rate, the larger the wavelength of the different colors. The oxide film thickness tends to increase and is not uniform to produce different optical path differences in the cutting process, appearing different colors on the surface of oxide film.