Fabrication of a superhydrophobic mesh via magnetically aided electrode electric discharge machining

Abstract

Fabrication of micro-structures is crucial to controlling surface wettability. Magnetically aided electrical discharge machining (EDM) is proposed for texturing of surfaces with complex geometries. In this approach, a magnetic field helps powder to accumulate on an electrode tip. The powder is flowable and can conform to the surface. In our experiments, a metal mesh was used as substrate and modified to be superhydrophobic so that it could be used to perform separations. Various mesh and powder sizes from rough to fine were tested to optimize compatibility between the electrode and substrate. The surface morphology, pore size, and wettability of the textured metal mesh were investigated using scanning electron microscopy and a contact angle meter. The textured mesh exhibited improved contact angle stability, anti-corrosion performance and mechanical stability. Various mesh sizes were tested for separation speed and efficiency. In addition, durability after cyclical use and universal separation capabilities were demonstrated.