Wire Electrochemical\nMachining of Multiscale Superhydrophobic\nArrays with Specific Unit Shapes on Stainless Steel

The multiscale superhydrophobic array with a specific\nunit shape\nhas a broader prospect for application in engineering materials, such\nas stainless steel (SS). However, the fabrication of the multiscale\nsuperhydrophobic array with a specific unit shape remains limited\nby several aspects, mainly including the complexity and controllability\nof multiscale integration of microstructures and arrays, the difficulties\nin obtaining specific unit shapes, and the low safety. Therefore,\nthere is an urgent need for a relatively controllable, simple, and\nsafe method to achieve a multiscale superhydrophobic array with a\nspecific unit shape. Here, a safe and controllable method of integrating\nthe array and microstructure into a multiscale superhydrophobic array\nis proposed by only wire electrochemical machining (WECM) in a harmless\nneutral electrolyte with controllable construction of different unit\nshapes. Here, first, the simulation and experiment of unit shapes\nby WECM is conducted to reduce the complexity of selecting parameters\nfor different unit shapes; then, an integration of the microstructure\nand array is conducted; finally, hydrophobicity performances of multiscale\nsuperhydrophobic arrays are tested, including the drop loading test\nand drop impact test. The results show that multiscale superhydrophobic\narrays by WECM exhibit excellent anti-intrusion performance and reduce\nsolid–liquid contact time significantly, indicating only WECM\ncan construct multiscale superhydrophobic arrays on SS with good controllability\nand safety.