Influence of polarization curve slope on the accuracy of local copper electrodeposition from sulphate electrolyte

Local electrochemical deposition is an emerging technique, used in the field of additive manufacturing. The advantage of electrochemical additive manufacturing lies in the utilization of room temperature electrolyte and permits to manufacture microscale objects with high precision. The increase in deposition current increases the deposition area, so measures are to be taken to focus the electric field. This work describes the influence of polarization curve slope on the accuracy of local deposition, both experimentally and by computer modelling. The copper was deposited using rotating anode on the surface of stainless steel from sulphate electrolyte. The influence of electrolyte composition on the accuracy of deposition was investigated. The profile of deposited parts was analyzed by profilometry and microscopy. The increased amount of sulfuric acid and presence of the additive in the electrolyte was shown to increase the accuracy of deposition by changing the slope of cathodic polarization curve from 320 to 1100 mA V–1cm–2)

Additive concentration and nozzle moving speed influence on local copper deposition for electrochemical 3D-printing

The local deposition process from copper sulfate electrolyte was investigated depending on nozzle moving speed and additive concentration in the electrolyte. A 2×2 cm square model was created and sliced in Ultimaker Cura software, uploaded in a 3D printer, and printed from the copper electrolyte on the stainless-steel surface. Low additive concentration in the electrolyte was found to influence dendrite formation in the corner sections of a square model. Nozzle movement speed was found to influence the deposition area and the thickness of the metal. The lowest tested nozzle movement speed of 5 s / voxel increased the deposition area by nearly 40 % in horizontal direction compared to 2.5 s / voxel. Further increase of nozzle movement speed to 1.6 s / voxel does not change the deposition area. The thickness in the corners increases by 2.5 times compared to the straight section of the square when the nozzle movement speed increases from 5 to 1.6 s / voxel. The non-uniform thickness of the deposited metal is caused by a considerable reduction of nozzle movement speed when it moves through the corner. The results obtained in this work can be further used to develop electrochemical 3D printing technology

Local electrochemical deposition of copper from sulfate solution

Local electrochemical deposition is a type of electroplating used to plate metal locally or form metal objects using electrochemical principles at a short distance from the working electrode. In this work, deposition of the copper spot was modelled using COMSOL software and experimentally tested in copper sulfate electrolyte using soluble copper anode. The working capillary diameter was 4 mm and the interelectrode distance was 5 mm. The deposited copper of 100 µm thickness was investigated using the 3D-profilometry technique. The geometry of deposited metal was found to be in good accordance with the COMSOL model. The inclusions of anodic sludge were responsible for the surface inhomogeneity of the deposited copper