Multipass scratch test behaviour of TiAlN thin film deposited on 316L stainless steel and Ti6Al4V alloy with dc biased and pulsed magnetron sputtering

In this study, TiAlN thin film was deposited with dc magnetron sputtering on 316L stainless steel and Ti6Al4V alloy which are widely used as hip joint implants. The adhesion behaviour of TiAlN thin films was investigated by multipass scratch tester. Multipass scratching with three progressive loads was performed on each sample. Observations of the scratch tests showed that there were three main failure events which were identified and labelled as L-c1, L-c2 and L-c3. Failure mechanisms were discussed according to SEM examinations of the scratch tracks. The TiAlN films with dense and homogeneous structure preferentially grew on the plane of (200) for 316L stainless steel and (111) for Ti6Al4V alloy. During the multipass scratch test, the friction coefficients were measured between 0.02 and 0.05. The best values for the friction coefficient were obtained from the films preferentially deposited on the plane of (111). After the scratch test, the thin film was damaged by mechanisms of chipping, flaking and spalling.