Non-invasive improvement of machining by reversible electrochemical doping: A proof of principle with computational modeling on the example of lithiation of TiO2

Abstract

We show in a combined density functional theory – molecular dynamics computational study that a small amount of lithium intercalated in TiO2, which preserves the host structure and can be introduced reversibly, in particular, by electrochemical doping, leads to a lowering of the strength of work materials and the cutting force. This is in spite of the fact that modifications of the elastic constants at room temperature are small, i.e. the effect is mostly on plastic properties. This approach is expected to be applicable to a class of ceramics exhibiting similar mechanisms of host-dopant interactions and presents a reversible and non-destructive way of modifying mechanical properties and improving machinability of hard ceramics.