In situ fabrication of copper electrodes on carbon-fiber-reinforced polymer (CFRP) for damage monitoring by printing and flash light sintering

The electrical resistance change method (ERCM) is a promising method for structural health monitoring (SHM) of composites. In this work, copper (Cu) nano-ink was printed and successfully sintered on carbon-fiber-reinforced polymer (CFRP) substrate for damage sensing via a flash light sintering method. Before printing, surface-polished CFRP substrate was flash light treated to remove remnant epoxy between carbon fibers. Then, Cu nano-ink was formulated and printed on the CFRP substrate, and the printed Cu nano-ink patterns were sintered within a few milliseconds using a range of flash light irradiation energies. A two-step flash light sintering method to reduce contact resistance between the Cu electrode and CFRP interface was further investigated. Fabricated Cu electrodes were characterized using scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). Using a two-step sintering approach, we fabricated Cu electrodes on CFRP with low contact resistance (0.93 Omega), high durability, and no mechanical degradation of CFRP substrate. (C) 2017 Elsevier Ltd. All rights reserved.