Effects of nano-TiO2 additive in oil-in-water lubricant on contact angle and antiscratch behavior

Authors

Wenzhen Xia, University of WollongongFollow
Jingwei Zhao, University of WollongongFollow
Hui Wu, University of WollongongFollow
Xianming Zhao, Northeastern University
Xiaoming Zhang, Northeastern UniversityFollow
Jianzhong Xu, Northeastern UniversityFollow
Ay Ching Hee, University of WollongongFollow
Zhengyi Jiang, University of WollongongFollow

RIS ID

109090

Publication Details

Xia, W., Zhao, J., Wu, H., Zhao, X., Zhang, X., Xu, J., Hee, A. & Jiang, Z. (2017). Effects of nano-TiO2 additive in oil-in-water lubricant on contact angle and antiscratch behavior. Tribology Transactions, 60 (2), 362-372.

Abstract

Contact angle and scratch tests have been conducted to investigate the effects of nano-TiO₂ additive in oil-in-water (O/W) lubricant. The results show that the contact angle between high-speed steel with oxide scale and 1% (oil concentration) O/W lubricant decreases first and then increases as the concentration of nano-TiO₂ particle in the O/W lubricant increases. The smallest contact angle is obtained after an addition of 4% nano-TiO₂ additive to the O/W lubricant. This is because the nano-TiO₂ can enhance the surface excess of the oil when the nano-TiO₂ particles distribute throughout the surface of the oil droplets, and after saturation they can distribute throughout the water and also improve the surface excess of the water in the O/W lubricant. The scratch and hot rolling tests show that the nano-TiO₂ particles in the O/W lubricant can also reduce friction, improve scratch resistance, and reduce rolling force. A method for measuring the adhesion force of the oxide scale is proposed and the effect of nanoparticles is discussed. It is demonstrated that the effect of self-lubrication of nanoparticles in the O/W lubricant plays a more significant role in the tribological behavior during hot rolling than wettability.