Mechanisms of remarkable wear reduction and evolutions of subsurface microstructure and nano-mechanical properties during dry sliding of nano-grained Ti6Al4V alloy: A comparative study

A comprehensive investigation into dry sliding wear and associated evolutions of subsurface microstructure and nano-mechanical properties of a bulk nano-grained Ti6Al4V alloy (NG-Ti6Al4V) was conducted. Comparing with its coarse-grained counterpart (CG-Ti6Al4V), NG-Ti6Al4V always exhibited lower friction coefficient and greater wear resistance in a wide range of tribological conditions. It was also found that the sliding wear induced nanomechanical properties and microstructure evolutions in Ti6Al4V alloy were largely dependent on its initial microstructural features. For the first time, TEM observations provided a direct experimental evidence that the originally saturated nanostructure in NG-Ti6Al4V could be further refined by sliding wear. This study proposed an effective strategy to improve the load-bearing ability of Ti6Al4V alloy by producing bulk homogeneous nanostructure.

Automated summary

The study found that the powder nano-grained Ti6Al4V alloy has lower friction coefficient and higher wear resistance compared to its coarse-grained counterpart, and that sliding wear can alter its nanomechanical properties and microstructure evolution, which depends on the initial microstructural features.