The Effect of Sonication Time on Thermal Conductivity and Stability of Graphene (Gr) and Aluminium Nitride (AlN)

Abstract

Nanolubricants are a critical topic currently due to their outstanding thermal conductivity and system performance. A highly stable nanolubricant dispersion is extremely useful for good lubrication performance. However, maintaining their dispersion stability over time is still a major challenge in this field. As a result, the goal of this paper is to evaluate the influence of sonication duration on the stability and thermal conductivity of nanolubricants. In this work, 0.1 vol% concentrations of graphene (Gr) and aluminium nitride (AlN) nanoparticles and polyolester oil (POE) as the base fluid are used. The duration of mechanical stirrer is constant however the ultrasonication time is varied. The stability of nanolubricants are observed by using visual observation technique for 21 days and measured by thermal conductivity and Zeta potential. The results show that the 45 min of sonication time for AlN and 15 min of sonication time for Gr are the optimum time for the ultrasonication.