Effects of non-flat contact and interference on self-assembled monolayers under sliding friction

▶ The contact area and exerted normal force increase with decreasing the tilt angle of the slider. ▶ The periods of normal force and shear force are delayed as the tilt angle of the slider increases. ▶ The contact interference increases, the normal force and shear force increase together. ▶ Short SAM molecules are more sensitive to a compressive loading and react to a larger normal force.