Fabrication and drag reduction of the superoleophobic surface on a rotational gyroscope

Surface tension and friction are dominant forces at microscale. The friction and wear of solid–solid or solid–liquid contacts affect the performance and lifetime of a microgyroscope. In this paper, we propose a novel superoleophobic liquid-bearing microgyroscope, and present a simple method to fabricate a superoleophobic surface on a 2J85 ferromagnetic alloy substrate through hydrofluoric acid etching. The superoleophobic surfaces exhibit reduced viscous drag because of the ‘slip’ associated with a layer of air trapped at the liquid/solid interface. In addition, a drag reduction ratio of approximately 10.7% was observed at a high velocity.