Abstract
During the sheet forming of composites, various deformation mechanisms must occur to reach the desired shape without flaws; such as, in-plane waviness and out-of-plane wrinkling. Understanding of these deformation mechanisms is required to reduce the failure rates of the composite parts and to optimize the processing parameters. In this study out-of-autoclave 8-Harness satin woven carbon-epoxy prepregs were investigated to determine their in-plane shear properties using the picture frame test. The load responses at various displacement rates were determined on fabrics of varying areal density. The locking angle at which adjacent yarns come in contact with each other with no further deformation which eventually leads to wrinkling has been investigated. The effect of temperature on wrinkling was determined using the sequential images taken by digital image co-relation (DIC). The study shows that angle of lock-up is prolonged with the increase in temperature.