Corrosion Behavior of the Ti-6Al-4V Alloy in Sulfate-Reducing Bacteria Solution

The corrosion behavior of the Ti-6Al-4V alloy was investigated in a sulfate-reducing bacteria (SRB) solution. The results showed that sulfate-reducing bacteria has good affinity with the surface of the Ti-6Al-4V alloy after 5 days. A potentiodynamic polarization test demonstrated that the corrosion resistance of the Ti-6Al-4V alloy was initially improved but deteriorated quickly in the subsequent period. The corrosion mechanism of the Ti-6Al-4V alloy was revealed by analyzing its microstructure with the aid of scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray fluorescence. The pitting corrosion was deemed to be a typical cause of the corrosion behavior of the alloy in the SRB solution. The underlying mechanism of the pitting corrosion was proposed for the alloy.