Laminate Blending Demonstrator

Abstract

The use of fiber-reinforced composites in the aerospace industry has increased over the past couple of decades thanks to their high specific properties. Fiber-reinforced composites also enable engineers to tailor the stacking sequence to satisfy the required stiffness or strength requirements. However, locally optimizing the stacking sequence of composite laminates introduces incompatibilities between the locally optimized sections which jeopardize the structural integrity of the panel. This highlights the importance of “laminate blending” which is a term given to problems that involve the local optimization of laminates while taking into account continuity guidelines to ensure manufacturability. In this work, a constant thickness blended demonstrator of 32 layers and 5x5 sections was designed, manufactured and tested for its stiffness and critical buckling load. The results were compared to a constant stiffness conventional laminate of the same geometry and weight. The critical buckling load of the blending demonstrator was 80.9% higher than that of its conventional counterpart and the stiffness was 93.75% higher.