Tribological properties of carbon nanotube/SiO2 combinations as water-based lubricant additives for magnesium alloy
Hongmei Xie, Yongyi Wei, Bin Jiang, Changping Tang, Chaoyin Nie
Abstract
The major objective of this work was to evaluate the tribological properties of the carbon nanotube/spherical SiO2 nanoparticles combinations as lubricant additives in deionized water. The tribological experiments were carried out on a linear reciprocating ball-on-plate tribometer at magnesium alloy/steel interfaces. The results demonstrate that dispersion of CNT/SiO2 combinations in deionized water exhibited superior tribological properties as well as the load-bearing capacity and lubrication film stability than individual CNT or SiO2 nanofluids. It especially emphasizes the outstanding tribological properties of the CNT/SiO2 combinations with a mass ratio of 0.2:0.3. The friction coefficient is decreased by 30.6% and the wear volume is decreased by 52.5%, when compared to the 0.5 wt % CNT nanofluids. The enhanced performances are most likely driven by the sliding-induced tribofilm of CNT and the possible ball bearings effect of nano-SiO2. These findings could provide new insights into the understanding and application of carbon nanomaterials-based combinations as water based lubricant additive and help to develop specific lubricants for magnesium alloy forming.