Optimized composites with the largest material usage efficiency

Abstract This paper is aimed to seek for the optimized composite microstructure for highest material usage efficiency. An energy-measured material usage efficiency is proposed as the criterion for structural optimization design, and we believe it is the best choice among all single parameters to evaluate the performance. The staggered bio-composites consisting of rectangular platelets and soft matrix have been widely studied, and proved to possess good mechanical properties. It is found that this staggered structure can be further optimized to achieve higher material usage efficiency. Based on the shear-lag analysis, the optimization shows that the optimal platelet shape is rhombic, which leads to more uniform stresses in both the platelet and the matrix compared with the widely used platelet shape, i.e. rectangle. The rhombic platelet case also possesses higher stiffness and strength than that of the rectangular platelet case.