ELASTIC PROPERTIES OF 3-DIMENSIONAL ANGLE-INTERLOCK FABRIC PREFORMS

An investigation is reported in which a model based upon fabric geometry was developed to predict the thread-volume fraction and elastic constants of three-dimensional angle-interlock fabric composites. The architecture of this model was investigated by identifying the structural and geometric parameters. The structural parameters include the total number of weft threads in the preform and the number of weft threads interlocked by warp threads in the thickness direction. A lenticular geometry was assumed for warp and weft threads in order to represent thread-flattening. Elastic constants were determined by using the averaging method and tensor transformations. Parametric studies were performed to examine the effects of various structural and geometrical parameters on the effective elastic properties of the composite.