Tribological Properties and Lubrication Mechanisms of Water-Based Nanolubricants Containing TiO2 Nanoparticles during Micro Rolling of Titanium Foils.

The tribological behavior of traditional oil-in-water (O/W) lubricants (1.0 wt.%) and nano-TiO2 additive lubricants (1.0-9.0 wt.%) during micro rolling of titanium foils were analyzed. In this study, the surface morphologies of titanium foils under various lubrication conditions were assessed, and the corresponding lubrication mechanisms were revealed. The tribological behavior of nano-TiO2 additive lubricants during micro rolling of titanium foils was also explored through a series of characterization methods. The utilization of nano-TiO2 additive lubricants in micro rolling reduces the surface roughness of titanium foils. Moreover, it effectively inhibits the generation of indentations and cracks during rolling processes, enhancing the surface quality of rolled specimens. Additionally, owing to the synergism of rolling, tribo-film, mending and polishing effects of the nanoparticles, both the rolling force and surface roughness were minimized by using lubricants containing 3.0 wt.% TiO2 nanoparticles. Overall, an optimal concentration (3.0 wt.%) of TiO2 nanoparticles in water-based nanolubricants was obtained with enhanced tribological properties and lubrication performance during micro rolling of titanium foils.

Study on the Tribological Behaviour of Nanolubricants during Micro Rolling of Copper Foils.

Water-based lubricants with different fractions of TiO2 nanoparticles ranging from 1.0 to 9.0 wt.% were utilized to study the lubrication mechanisms during micro rolling tests and the tribological behaviour of nanolubricants during the micro rolling of copper foils. The results indicate that the application of TiO2 nanolubricants remarkably improves the surface quality of rolled copper foils during rolling processes. For lubricants with inadequate TiO2 nanoparticles, it is found that few TiO2 nanoparticles enter the contact regions between the rolls and foils, causing insufficient lubrication during rolling processes. Instead, for lubricants with excessive TiO2 nanoparticles, obvious agglomeration occurs at the contact regions and promotes the generation of voids on the surface of the rolled foils, thereby deteriorating the surface quality of the rolled copper foils. In addition, it is found that the surface quality of rolled foils is improved by utilizing a large reduction ratio. Overall, the fraction of 3.0 wt.% TiO2 nanolubricants is optimal to improve the lubrication conditions at the contact regions, thereby improving the surface quality of the rolled copper foils.