Study on the enhanced tribological performance for titanium alloys by PEG oil/Zn-nanoparticles

This work developed an effective and promising lubricant containing Zn nanoparticles and polyethylene glycol (PEG) base oil to deal with the tough problem of boundary lubrication for steel/Ti6Al4V. Tribological tests were carried out to investigate the boundary lubrication performances and the generation process of boundary protective films on the worn surface. Results showed that low and steady friction coefficient curves could be obtained by PEG suspensions with Zn nanoparticles after a very short 'run-in' period, and the main wear volume of Ti6Al4V was occurred during the 'run-in' period. The ZnO boundary protective films generated on the counterfaces of the Ti6Al4V disk and steel ball during the friction process. This strong and steady oxide films could effectively prevent direct contact between frictional pairs and provide excellent boundary lubrication performances. This work will contribute to the development of high performance lubricants for titanium alloys (paper)