The co-cure of honeycomb sandwich structures: process physics and manufacturing strategies

The co-cure of honeycomb sandwich structures involves complex physical phenomena and poses challenges for manufacturing process development. This paper describes results from a multi-year research project on co-cure, during which in situ observations, processing trials, and microstructural analysis were used to understand key physics and defect formation mechanisms. Results show that co-cure is governed by interactions between core pressure evolution, bond-line formation, and facesheet consolidation, and that defect evolution is path-dependent and challenging to control. However, results also demonstrate a manufacturing strategy for successful and reliable co-cure. Overall, the paper clarifies the fundamental science associated with co-cure of honeycomb sandwich structures, and provides a viable pathway for optimizing manufacturing processes.