Localized and Mask-less Copper Deposition with Free-flow Jet Micro-Electrochemical Additive Manufacturing

抄録

Micro-electrochemical additive manufacturing (μECAM) is reverse of electrochemical micro-machining (μECM) which is used for selective and localized deposition of material on a substrate. It can be used to manufacture small sized parts or deposit functional metal coatings on conductive surfaces. As the process is contactless and generates negligible joule heating, the deposited material is free from heat affected zones and has low internal stresses. This work presents a free-flow jet micro-electrochemical additive manufacturing (FJECAM) process that deposits material through a continuous stream of electrolyte. FJECAM can deposit accurate μm to mm scale features without the need for expensive masking and complex meniscus control as used in traditional μECAM configurations. This facilitates rapid surface modifications, surface coatings and deposition of 2D-2.5D shapes with high accuracy. In this paper, the deposition mechanism of copper (Cu) on stainless steel substrate (S.S.) during FJECAM is investigated through the characterization of surface topography and analysis of process current. The micro-deposits with FJECAM at different voltages and scan rates were observed to be without porosities and a minimum surface roughness of 0.38 ± 0.02 μm was achieved at a material deposition rate (MDR) of 16.06 μg/s which is 20 times higher than the traditionally used meniscus-confined μECAM (MECAM) at the same process parameters.