Electrochemical Polishing of Microcomponents

Abstract

Microcomponents can be fabricated by traditional methods like micromilling/drilling, or by nontraditional methods like electrical discharge micromachining (EDM), laser micromachining, or electrochemical micromachining (ECM). These methods, however, often leave detrimental residual defects like sharp burrs, cracks in heat affected zones, in addition to rough surface finish. Electrochemical polishing (ECP) offers a non-contact technique to remove surface defects such as burrs, rolling/grinding/machining marks regardless of component size. This study develops an ECM/ECP technique to fabricate or polish microcomponents, and implements this technique to polish copper, titanium, and stainless steel microcomponents fabricated by EDM and micromilling. Assessment is made by optical microscopy, electron microscopy, atomic force microscopy, and interferometry. Burrs and surface defects of the tested microcomponents are effectively removed by ECP. Surface finish of polished surfaces of polycrystalline titanium, copper, and stainless steels is in the range of 100-300 nm Ra on polycrystalline surface and 1-10 nm Ra within a single grain.