LIPSS combined with ALD MoS2 nano-coatings for enhancing surface friction and hydrophobic performances

To enhance the friction and hydrophobic performances of contact interfaces, the laser-induced periodic surface structures (LIPSS) by picosecond pulses and atomic layer deposition (ALD) MoS2 nano-coatings are fabricated on the cement carbide surface. The friction and wettability tests are carried out by the unidirectional sliding friction and sessile drop experiments. Results show that the friction and wetting properties can be regulated by the LIPSS and ALD MoS2 nano-coatings, and the anisotropic friction and hydrophobic properties are observed with respect to the groove orientations. A combination of ALD MoS2 nano-coatings with LIPSS in parallel orientation (MS-HT) exhibits the best potential for improving the friction and wear performance, and the ALD nano-MoS2 coated surface combined with LIPSS in perpendicular to the observation direction (MS-VT) is the most effective way for enhancing the hydrophobic property.