MEASUREMENT OF COMPOSITE INTERFACE FAILURE BY QUANTITATIVE AE

In this paper we report on the study of composite interface failure pr ocesses using quantitative acoustic emission (AE) measurements. The de struction of model composite specimens is studied in order to isolate the constituent interactions. A number of previous fiber pullout studi es of composite interface failure have relied on fiber force and displ acement data to elucidate fiber/matrix properties. In our study, we us e ultrasonic waves that emanate from the failure region to determine t he forces that are released as the interface fails. We avoid assuming a specific model for the micro-processes; rather, the forces are deter mined directly from the acoustic emission signal detected at a distanc e from the source.