The use of carbon nanotubes to sense matrix stresses around a single glassfiber

The stress field in a polymer matrix in the vicinity of a single glass fibe r was mapped on the micron scale by using the strain-response of the Raman spectrum of single-wall carbon nanotubes (SWNTs) embedded in the matrix. A stress concentration zone is observed around the fiber end. Far away from t he fiber, the applied stress value is recovered. The importance of this tec hnique and the measurements for composite design and micro-mechanical model s is discussed. (C) 2001 Elsevier Science Ltd. All rights reserved.