Effect of heat treatment on microstructural and electrochemical properties of titanium and Ti alloy

The electrochemical and microstructural properties of commercially pure Ti and Ti-6Al-4V were evaluated after different heat treatment (HT) conditions. In Ti, the standard HT and 900 °C HT groups showed an equiaxed recrystallized α-phase grain structure. In the 1000 °C HT group, needle-like structures were observed. In the 1200 °C HT group, thick needle-like microstructures with some serrated grain boundaries were observed. In the Ti alloy, growth of the α+β phase was observed in the 900 and 1000 °C HT groups. In the 1000 °C HT group heated above the phase transition temperature, the microstructure showed considerable β phase dispersion into the α phase. In the 1100 and 1200 °C HT groups, characteristic Widmanstatten structures were observed.