Deformation characteristics and formability of fibre-reinforced thermoplastic sheets

Abstract

In order to quantify the deformation in sheet materials when formed into complex shapes, an experimental measurement technique is necessary. This paper presents the findings of large strain analysis when applied to thermoplastic composite sheets. Three materials have been investigated by forming flat laminates into a circular cavity with a hemispherical die. With increasing blank size and forming speed, and a decreasing forming temperature, the loads of deformation increased. These data have been presented and related to the problem of flange wrinkling in conjunction with the strain analysis results. Arrow diagrams, and strain contour maps clearly identify the regions of severe deformation, and highlight large compressive strain gradients where buckling occurs.