Stability analysis of CuO suspended API GL-5 gear lubricant sol

In this work, a mineral oil based gear lubricant sol is prepared by dispersing solid phase CuO particles in commercially available API GL-5 gear lubricant as a continuous liquid medium. Multifunctional micellar CuO particles are synthesized by sol-gel method and CuO-gear lubricant sol with various concentrations are prepared by ultrasonic agitation. The suspension, chemical and thermal stability of lubricant sol are analysed in UV-visible spectroscopy, Fourier Transform Infrared Spectroscopy, Thermogravimetric Analyser (TGA), and Differential Scanning Calorimeter (DSC), respectively. The chemical structures of samples retained reflect notable chemical stability and the agglomeration of CuO micro particles is observed above 0.3 wt% by the effect of interface minimization which deteriorates thermo stability. Further, transition enthalpy, melting and decomposition parameters are acquired through thermograms and discussed. These results designate that the ability of absorbing and releasing thermal energy being enhanced up to 0.3 wt% and further get decreased.