Fig. 3
a Changes in the average wear volume as a function of different SiO2/MoS2 mixing ratios and 3D optical microscopic images of the wear tracks corresponding to b base oil, c pure SiO2, d pure MoS2, and e SiO2/MoS2 (0.25:0.75) (8 N, 30 mm/s, 1.5 h)