FATIGUE LIFE PREDICTION OF CROSS-PLY COMPOSITE LAMINATES

To predict the fatigue life of fiber reinforced composites, fatigue pr ocess of CFRP laminates of [0 degrees/90 degrees](s) is investigated a nd the influence of damages occurring at fiber, matrix and fiber/matri x interface on the various critical strengths and the relationship bet ween residual critical strength and failure are discussed. As a result , it was shown that fatigue strength (i.e. fatigue life) consisted of residual critical strength and stresses occurring at each layer (0 deg rees and 90 degrees layers) and interlayer. Moreover, the fatigue fail ure occurred because the residual critical strength of each layer and interlayer decreased with dependence of their microdamage densities, s o that the fatigue life can be predicted by evaluating microdamage beh avior in fatigue process. (C) 1997 Elsevier Science S.A.