Prediction of Delamination in Composite Laminates Subjected to Low Velocity Impact

A method for predicting impact-induced delamination in composite lami nates was proposed. This method is suitable for low velocity impact with heavy impactors. Static delamination fracture toughness was used to predict delamination crack growth under impact conditions. Curing stresses were also considered and found to play a signifi cant role in evaluating the fracture toughness of some laminates such as [905/05/90 5]. Ex periments were performed to obtain the impact force history from which the peak force was used to determine the extent of delamination crack length. The prediction of delami nation size using static fracture toughness was found to agree very well with the experi mental result.

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