Triboelectricity during Brittle Fracture of an Epoxy Resin.

Abstract : Previous observation of time dependent voltages induced on metal probes positioned near fiber/plastic composite specimens during stressing made imperative the determination of their physical significance. One possible source of such signals was cracks in the resin matrix phase of such materials, since fracture of cast epoxy resins had produced similar signals. The objective of this work was to determine the physical significance of induced voltage-time signals accompanying a simple fracture process. Fracture of a brittle epoxy resin which exhibited nearly glasslike fracture was studied. The fresh fracture surfaces were found to be electrically charged. The induced voltage-time signals were generated as the charged fracture surfaces separated, following propagation of the single crack which produced fracture. (Author)