Mechanical performance of composites based on various three-dimensional woven-fibre preforms

Over the last ten years several textile technologies have been developed in order to manufacture textile preforms for three-dimensionally reinforced polymer-, ceramic- and metal-matrix composites. The aim was, on the one hand, to improve the mechanical performance, above all the damage tolerance and, on the other hand, to decrease manual work during the manufacturing process compared to two-dimensional laminates. The scope of this paper is to review the mechanical performance of various three-dimensional (3D) woven composites (monolithic and sandwich) by comparison of in-plane properties (stiffness and strength), damage tolerance, energy absorption capability and fracture mechanical properties. In the first part of this paper is demonstrated the general influence of the 3D reinforcement on mechanical performance. Because of the unique interlaminar failure behaviour, state-of-the-art testing methods need to be reviewed critically: in order to determine the interlaminar shear strength a new testing method seems to be necessary. In the second part of the paper, various monolithic 3D composites manufactured by using different weaving types are compared, while in the third part the mechanical performance of a special class of 3D weavings, the integrally woven sandwich structures, will be discussed.