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Ni–Co coating or texturing surface has been studied extensively to improve the anti-friction ability of the surface. In this paper, we combine the advantages of Ni–Co coating and textured surface, and then use a simple, novel and easily controlled method to fabricate a series of micro/nanoprotrusions on the Ni–Co coating surface. The nanotribology properties were characterized by AFM. The result shows that the micro/nanotextured surface significantly reduced the friction forces compared with the original Ni–Co coating surface. The half-ellipsoid patterns have better tribology properties than half-hemispherical patterns. Both laser power and laser scanning speed were found to influence the friction performances.

We employ an ultrafast laser with 1 kHz repetition rate and 130 fs pulse width to fabricate micro/nanotextures and unique surface structures on silicon surfaces under different environments. First, we study the effect of vacuum and fabricate micro-spike structures at 800 nm wavelength and a pressure of 4 ⋅ 10−3 Pa. We observe even sub-100 nm ripple structures on micro-spikes after 800 nm laser irradiation in distilled water because the produced bubbles are expelled from the chamber. Finally, we show that submicron-spike structures fabricated after 400 nm laser irradiation in distilled water are smaller than those in vacuum.