Laminate design using carpet plots Carpet plots can represent tensile modulus and tensile strength for a family of laminates with the same basic ply orientations. Such charts are quite useful in selecting the proportions of the various ply orientations required to meet the particular design criteria involved. Determine the carpet plot for tensile modulus Ex of a carbon fiber-epoxy [0m /90n /(45)p ]S laminate family. Notes: ? Use properties of unidirectional graphite/epoxy lamina from Table 2.1 and assume that each layer is 0.125 mm thick. ? Percentage of 90 plies = 100 - (percentage of 0 plies) - (percentage of 45 plies). ? The figure to the right is an example of carpet plot for a [0m /90n /(45)p ]S laminate family.

Tensile modulus, Exx (Msi) 30 30 20 20 100 90 10 20 20 207 0 x Percent 0 plies 138 80 70 60 50 40 69 30 20 10 0 40 60 80 100 Percent 45 plies Exx (GPa)