Effects of stacking sequence on impact damage resistance and residual strength for quasi-isotropic laminatesResidual strength of an impacted composite laminate is dependent on details of the damage state. Stacking sequence was varied to judge its effect on damage caused by low-velocity impact. This was done for quasi-isotropic layups of a toughened composite material. Experimental observations on changes in the impact damage state and postimpact compressive performance were presented for seven different laminate stacking sequences. The applicability and limitations of analysis compared to experimental results were also discussed. Postimpact compressive behavior was found to be a strong function of the laminate stacking sequence. This relationship was found to depend on thickness, stacking sequence, size, and location of sublaminates that comprise the impact damage state. The postimpact strength for specimens with a relatively symmetric distribution of damage through the laminate thickness was accurately predicted by models that accounted for sublaminate stability and in-plane stress redistribution. An asymmetric distribution of damage in some laminate stacking sequences tended to alter specimen stability. Geometrically nonlinear finite element analysis was used to predict this behavior.
Document ID
19920056400
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Dost, Ernest F. (NASA Langley Research Center Hampton, VA, United States)
Ilcewicz, Larry B. (NASA Langley Research Center Hampton, VA, United States)
Avery, William B. (Boeing Co. Seattle, WA, United States)
Coxon, Brian R. (Integrated Technologies, Inc. Bothell, WA, United States)