The influence of curing cycle and through thickness variability of properties in thick laminates

Abstract

Mechanical properties of glass fibre reinforced polymers are dependent on the manufacturing curing cycles. During the laminate manufacturing process, each thickness position experiences a different local curing cycle. Therefore, it can be expected that mechanical properties vary through the thickness, particularly for thick laminates. To study the through-thickness variation of static and fatigue mechanical properties, thick laminates were divided into sub-laminates and these sub-laminates were separately tested. The present work reports temperature profiles through the thickness recorded during the manufacturing of thick laminates, as well as experimental data from static and fatigue tests (S–N curves) of sub-laminates obtained at different thickness positions. The variation of the mechanical properties through the thickness is discussed and related to the local curing temperatures experienced by each sub-laminate.