Rheological behavior of 10W40 base oil containing different combinations of MWCNT-Al2O3 nanoparticles and determination of the target nano-lubricant for industrial applications

The main goal of this research is to compare the rheological behavior of hybrid nano lubricants (HNLs) with different composition ratios in a base oil. The purpose of the comparison is to determine the HNL with the best lubrication performance at the start of the vehicle. Theoretical methods have confirmed the non-Newtonian behavior in different laboratory conditions. HNLs with the composition ratio of 30:70 and 25:75 had the highest percentage of increase and decrease in viscosity, respectively 34.97% and − 1.85% at T = 55 °C, shear rate SR = 6665 s⁻¹ and solid volume fraction SVF = 1% and T = 5 °C, SR = 3999 s⁻¹ and SVF = 0.05%. To predict the viscosity of the desired HNL, in the RSM, a special model with an accuracy of R² = 0.9997 has been used. The margin of deviation (MOD) is determined in the range of − 3.43% < MOD < 4.75%. Viscosity sensitivity analysis shows that the greatest sensitivity will result from SVF changes at high SVFs. The experimental results of this study will introduce the optimal nano polishing to the craftsmen, and the theoretical part of this study will save the researchers from spending time and excessive economic costs.