Iranian Journal of  Manufacturing Engineering

Iranian Journal of Manufacturing Engineering

Experimental and numerical study of environmental parameters' influence on the surface morphology of mesostructures fabricated by integrating additive manufacturing and electroforming processes

Document Type : Original Article

Authors
Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
Abstract
With the rapid development of the microelectromechanical systems (MEMS) field, the demand for small-scale metallic components has significantly increased. Among the manufacturing methods for micro metal structures, the LIGA (Lithographie, Galvanoformung, Abformung) process, utilizing electroforming, offers high dimensional accuracy and surface smoothness; however, it has limitations such as expensive equipment and a lack of design flexibility. The integration of additive manufacturing and electroforming processes alleviates the limitations of the LIGA process in producing micro and meso metal structures. Environmental parameters during the electroforming process have a considerable impact on surface morphology, the occurrence of voids, and dendritic growth of the final product. In this study, the effects of various environmental parameters, such as the anode-cathode distance, the acidic or non-acidic nature of the electrolyte, copper sulfate concentration, and the state of the stirring system (on or off), on the surface morphology of microstructures produced through the integration of additive manufacturing and electroforming of copper were investigated. Additionally, to save on costs and testing time, numerical simulation of the electroforming process was conducted using COMSOL software to predict the thickness profile of the deposited layer during the process. Experimental results indicate that the addition of 78 grams of sulfuric acid to the electrolyte results in a significant improvement in surface smoothness. Furthermore, at low concentrations of copper sulfate (approximately 80g/l), dendritic growth becomes predominant on the layer. Experimental and numerical investigations on the effect of anode-cathode distance revealed that this parameter has a minor impact on surface roughness and thickness of the deposited layer. The numerical results showed a maximum error of 7.5 percent compared to the experimental model.
Keywords

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