MICROMECHANICAL CHARACTERIZATION OF LOCAL DEFORMATION IN INTERLAMINAR-TOUGHENED CFRP LAMINATES

The in situ SEM micro-line/grid methods were applied for quantitative evaluation of microscopic deformation in interlaminar-toughened CFRP c ross-ply laminates with transverse cracks. Both the local deformation in the interlaminar region around the transverse crack tip and the cra ck opening displacement (COD) were observed at different temperatures to evaluate the effect of thermal residual stress. A two-dimensional a pproximate elastic analysis of stress and displacement fields in inter laminar-toughened cross-ply laminates with transverse cracks was condu cted and compared with the experimental results. A reasonable agreemen t was obtained which implied the applicability of the analysis. The an alysis will be a basis for the optimal design of interlaminar-toughene d composite laminates. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.