Fabrication of graphene/nickel composite microcomponents using electroforming

This paper introduces combined processes to fabricate graphene platelet (GPL)/nickel (Ni) composite microcomponents. The process involves co-deposition of Ni and GPL into SU-8 micromolds to form the components, where SU-8 molds of 400 mu m in thickness were fabricated using UV lithography and an electrolyte with a GPL concentration of 0.2 g/L was used for the electroforming process. Pure Ni microcomponents were also fabricated under the same condition for comparison. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to examine the surface morphologies and microstructures of the microcomponents. Grain sizes were estimated based on the XRD results. A Raman microscope was used to characterize the GPLs in the GPL/Ni composite microcomponents. Hardness property was characterized using a Vickers hardness tester. Ni and GPL/Ni microcomponents of 200 mu m in thickness are successfully electroformed and show good shape retention and high precision. Microscopy examinations show that GPLs are evenly deposited in the Ni matrix and agglomeration of GPLs occurs during the electroforming process. The addition of GPLs leads to significant grain refinement of Ni matrix, and the microhardness value of the composite microcomponents is twofold higher than that of pure Ni microcomponents. The research results prove a novel method to fabricate high-precision microcomponents with excellent mechanical performance by introducing GPLs into Ni matrix.