Multi-material additive manufacturing of polymers and metals using fused filament fabrication and electroforming

This paper proposes an additive manufacturing method that combines fused filament fabrication (FFF) 3D printing and an electroforming technology to fabricate multi-material structures composed of resin and metal. In this method, an FFF 3D printer prints a resin mold that functions as a structural unit in a multi-material structure and as a sacrificial plastic mold for the addition of the metal material. This sacrificial mold is eventually removed. Electroforming the interior of a printed resin mold enables the fabrication of multi-material structures using resin and metal materials. The fabrication conditions for multi-material structures when using the proposed method were investigated and the surfaces of the resulting structures were evaluated. The fabrication conditions for the specified thickness per process and the total thicknesses from all the processes were determined. Furthermore, our results indicated that the shape of the side of the metal portion depended on the forming precision of the FFF 3D printer. We present an example of the fabrication of a gear shape from resin and metal.