Tribocorrosion behaviour of laser cladded biomedical grade titanium alloy

摘要

The tribocorrosion behaviour of laser cladded Ti6Al4V sliding against alumina ball in 3.5% NaCl has been assessed. Commercially pure (CP) Ti particles were laser cladded on Ti6Al4V using ytterbium laser system (YLS). The tribocorrosion behaviour of Ti6Al4V before and after treatment was investigated in 3.5% NaCl (pH = 6.24) and modified 3.5% NaCl (pH = 4) solutions using a pin-on-disk tribometer with integrated potentiostat. Potentiodynamic polarization curves indicated that the corrosion potentials of cladded Ti6Al4V decreased compared to that of the uncladded samples. Additionally, the corrosion current densities of cladded Ti6Al4V decreased significantly in both electrolytes investigated. The tribocorrosion behaviour of cladded Ti6Al4V did not change significantly. The wear depth of cladded Ti6Al4V decreased significantly in modified 3.5% NaCl whilst remaining unchanged in 3.5% NaCl. The coefficient of friction (COF) increased with time in Ti6Al4V whilst that of cladded sample decreased marginally with time in both electrolytes.