Evaluation of resistance measurement techniques in carbon black and carbon nano-tubes reinforced epoxy

Document Type

Conference Proceeding

Date of Original Version



Two different resistance measurement techniques are used in an epoxy material reinforced separately with carbon black (CB) micro-particles and carbon nano-tubes (CNTs) to evaluate the effectiveness of both the techniques and type of reinforcement on damage detection under uni-axial tensile loading. Two techniques, namely traditional four-point probe (FPP) and four-circumferential ring probe (FCRP) are employed and a constant current is applied through outer probes. The resulting voltage drop between inner probes is measured using a commercial high resolution electrometer based system. Since current density distribution in both techniques is different, the measured change in resistance (both qualitatively and quantitatively) is also different. In addition to change in current density due to different techniques, the size of conductive reinforcement also has significant impact on both current distribution and further change in resistance. CB reinforced epoxy showed very high percentage change in resistance against CNTs reinforced epoxy for both techniques. It was identified that CNTs reinforced epoxy showed no significant difference for both FPP and FCRP methods. However, for CB reinforced epoxy, significant difference in percentage change in resistance was observed for both resistance measurement methods.

Publication Title

Conference Proceedings of the Society for Experimental Mechanics Series