MECHANICAL PERFORMANCE OF COMPOSITES BASED ON VARIOUS 3-DIMENSIONAL WOVEN-FIBER PREFORMS

Over the last ten years several textile technologies have been develop ed in order to manufacture textile preforms for three-dimensionally re inforced 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 durin g the manufacturing process compared to two-dimensional laminates. The scope of this paper is to review the mechanical performance of variou s three-dimensional (3D) woven composites (monolithic and sandwich) by comparison of in-plane properties (stiffness and strength), damage to lerance, energy absorption capability and fracture mechanical properti es. In the first part of this paper is demonstrated the general influe nce of the 3D reinforcement on mechanical performance. Because of the unique interlaminar failure behaviour, state-of-the-art testing method s need to be reviewed critically: in order to determine the interlamin ar shear strength a new testing method seems to be necessary. In the s econd part of the paper, various monolithic 3D composites manufactured by using different weaving types are compared, while in the third par t the mechanical performance of a special class of 3D weavings, the in tegrally woven sandwich structures, will be discussed.