Vibration assisted high-speed wire electric discharge machining for machining surface microgrooves

A microgrooved surface structure has broad application prospects in areas such as surface hydrophobic drag reduction, catalyst loading, and heat dissipation. In this study, a low-frequency vibration-assisted technique with the advantages of high efficiency, low cost, and wide material adaptability was proposed for high-speed wire electric discharge machining (WEDM-HS) to fabricate microgroove surface structures on metal plates. First, a linear motor was utilized as the driving source to load low-frequency vibrations (less than 10 Hz) onto the wire to machine microgrooves. Then, the forming mechanism of the microgroove structure was established. Next, the effect of each of the main processing parameters, including the pulse-on time, pulse-off time and feed rate, on the groove depth, groove width and ridge width of the microgroove, was investigated. Experimental results revealed that the established model is approximately consistent with the experimental data. Furthermore, a microgroove surface hydrophobic structure was successfully fabricated using this method, and the test results indicated that this structure can significantly improve the hydrophobic properties of the metal surface. Thus, the use of this vibration device enables conventional wire-cutting machine tools to manufacture microgroove surface functional structures efficiently and inexpensively, while also facilitating the expansion of the processing range of the microgroove size.