A study on the tribological characteristics of duplex-treated Ti–6Al–4V alloy under oil-lubricated sliding conditions

• The effects of dimples and over-coated DLC film were investigated.
• Dimples were produced on a Ti–6Al–4V alloy specimen by LST.
• Cr-doped DLC film was deposited on a dimpled Ti–6Al–4V alloy specimen.
• Over-coated DLC film exhibited a significantly high resistance to wear.
• Over-coated DLC film led to a lower friction coefficient.

The tribological characteristics of the polished, dimpled and over-coated dimpled specimens were investigated. Dimples were produced on a Ti–6Al–4V alloy specimen using a laser surface texturing (LST). A Cr-doped diamond-like carbon (DLC) film was deposited on a dimpled specimen using an unbalanced magnetron sputtering (UBMS). The effects of dimples and over-coated Cr-doped DLC film on the tribological characteristics were investigated by performing the friction tests against a Cr-plated steel pin. The test results showed that the over-coated dimpled specimen exhibited a lower friction coefficient and wear compared to those of the polished and dimpled specimens, which may be attributed to the storage of wear debris and high hardness. A model of the wear reduction mechanism of the specimens was discussed.