Numerical simulation and experimental research on through-mask electrochemical machining of micro-dimple arrays using inner-jet cathodes

Abstract

The surface micro-dimple arrays can effectively improve the friction and lubrication performance of moving parts and are widely used in cutting tools and mechanical transmissions. Through-mask electrochemical machining (TMECM) is a process that uses the anodic dissolution principle to remove materials at low temperatures. It is suitable for efficiently processing large-area micro-dimple arrays on metal surfaces. However, the previous TMECM method still suffers from the problem of low processing adaptability. In this paper, a new method for scanning-cathode TMECM by utilizing the fluid dynamic pressure effect was proposed, and the flow field and electric field models of various inner-jet cathodes were developed as well. Through numerical simulations of the flow field and electric field, the flow velocity, electrolyte pressure, and current density distributions for different inner-jet cathodes were investigated to determine an appropriate cathode. Contrasting experiments were conducted to investigate the variations in electrolyte flow states and machining currents for different inner-jet cathodes. Additionally, the changes in micro-dimple dimensions under different machining parameters were investigated. Moreover, the micro-dimple arrays of 385.7 μm in diameter and 111.8 μm in depth, 288.8 μm in diameter and 40.3 μm in depth, and micro-dimple arrays with an etching factor of 1.69 were fabricated, and the results demonstrated the good processing adaptability of the scanning-cathode TMECM.