Elastic Modulus of Ribbon Reinforced Composites

The volume fraction of ribbon may be expressed as

(24.1)

where and are the width and thickness of the ribbon, is the spacing between two layers of the ribbons and is the spacing between two ribbons in a given layer.

Longitudinal elastic modulus of ribbon composites similar to continuous fiber composites may be determined using the rule of mixtures

(24.2)

where is the elastic modulus of ribbon, is elastic modulus of the matrix, is the volume fraction of ribbon. The in-plane behavior of ribbon composites is analogous to the behavior of aligned short fiber composites. Therefore, the in-plane transverse modulus may be calculated using the Halpin-Tsai equation

(24.3)

where,

(24.4)