The effect of substrate surface conditions on mechanical performance of electrically conductive adhesive

This project investigates the effect of surface treatment towards the surface roughness and surface wettability which contributed to the lap shear strength of electrically conductive adhesive (ECA) bonded to aluminum-aluminum substrate. Several surface treatment methods were applied on the aluminum substrate which involved chemical etching process with the utilization of NaOH solution and HCl solution, and mechanical abrasion process by SiC abrasive paper G180 and G1200. Four-point probe test on ECA sheet resistance shows that the increase of multi-walled carbon nanotube (MWCNT) filler loading decreased the ECA electrical resistivity. As chemically etched substrate provides highest surface roughness and the lowest contact angle, the ECA bonded to the substrate exhibit the highest shear strength when subjected to lap shear test.