Synergistic effect of hexagonal boron nitride and carbon nanofibers on tribological behavior of nanolubricant

The lubrication of the wind bearings is crucial for maintaining the efficiency and lifetime of the wind turbines. In this work, nanolubricant samples containing hexagonal boron nitride (h-BN), carbon nanofibers (CNFs), and carbon nanotubes (CNTs) were prepared and applied to friction pairs to study the tribological properties at different speeds and under different loads. The polyalphaolefin (PAO) sample with 6 wt% of CNF and 6 wt% of h-BN demonstrated the lowest and most stable average friction coefficient of GCr15/40Cr pair. Considering reduction of both wear loss and friction coefficient, the sample with only CNF is more suitable for low-load and low-speed working conditions. While the sample loaded with both h-BN and CNF is more suitable for high-load and high-speed working conditions.