Multi-objective optimization of weight and strength of laminated composites using gap-less and overlap-less variable thickness fiber placement

摘要

A variable-thickness carbon fiber placement technique was developed by adding new functions to the existing automated fiber placement. In this study we propose a multi-objective optimization method to achieve high strength and low weight for variable-thickness fiber placement using the Christensen fracture criterion and mean curvature (or weight) as the objective functions, and the fiber orientation and thickness distribution of the prepreg tape as design variables. The method was applied to the open-hole tension (OHT) problem. The optimization results showed that there is a tradeoff between strength and mean curvature: the higher the mean curvature, the higher the strength gain. In addition, the weight of the optimized layers of the OHT plates was reduced by up to 52.6% compared with the corresponding layers of the linear and constant thickness laminated OHT plates with improved strength.