Generating micro-dimples array on the hard chrome-coated surface by modified through mask electrochemical micromachining

It has been recently identified that micro-dimples can act as fluid reservoirs and promote the retention of a lubricating film to reduce friction between mechanical components. Various techniques are employed to produce micro-dimples on the surface of friction pair. In this study, a modified through mask electrochemical micromachining (TMEMM), in which the insulation layer was directly attached to the cathode, was developed to produce micro-dimples on the hard chrome-coated surface. By controlling machining parameters, micro-dimples array, with hundreds of micrometers in diameter and several micrometers in depth, were produced. Compared with the traditional TMEMM, the modified method can both reduce cost and improve machining efficiency. Friction experiments show that the friction coefficient of the surface with appropriate micro-dimples array is obviously lower than that with nondimples.