Improving machinability of titanium alloy by electro-pulsing treatment in ultra-precision machining

Titanium alloys have promising properties for optical applications but are difficult to machine. This paper proposes a new method for improving the machinability of titanium alloys in ultra-precision machining by applying electro-pulsing treatment (EPT). EPT is carried out to improve the plasticity of a typical titanium alloy, Ti6Al4V. Hardness and compression tests confirmed that yield stress and hardness are both reduced after EPT. Finite element modelling and ultra-precision machining were performed to study the machinability of Ti6Al4V before and after EPT. Lower cutting forces with lower power spectral densities, more continuous chips and better surface finish were obtained after EPT.