A nanograined (NG) layer with an average grain size of less than 100 nm has been successfully prepared on a Ti⁻6Al⁻4V sheet surface by sliding friction treatment (SFT). The electrochemical corrosion/passive behavior and mechanical properties of an NG Ti⁻6Al⁻4V sheet were examined in this study. A bi-layer passive film that consisted of an outer TiO₂-rich layer and an inner Al₂O₃-rich layer was formed on either an NG or coarse-grained (CG) surface. The improved corrosion was mainly caused by the enhanced stability and thickness of the passive layer. Tensile experiments were carried out to evaluate the mechanical properties at ambient temperature. The NG Ti⁻6Al⁻4V sample exhibited the high yield strength (956 MPa) with a moderate elongation of 8%. These superior comprehensive properties demonstrated its potential as a biomedical material.
Keywords: Ti–6Al–4V alloy; corrosion resistance; nanostructure; passive film; tensile properties.