Title: A Simple Analysis Tool to Simulate the Co-cure of Honeycomb Core Composite Sandwich Structures
Authors: Navid Niknafs Kermani, Pavel Simacek, and Suresh G. Advani
Abstract: Honeycomb sandwich structures are fabricated using a co-cure process by bonding partially cured thermoset prepreg sheets with an adhesive layer to either side of the honeycomb core structure under a selected pressure and temperature cycle. High defect levels during the co-cure are common as the process development cycle is strongly dependent on many material and process parameters such as prepreg facesheet consolidation, adhesive bond-line fillet formation, porosity level within the prepreg and the adhesive, and core pressure evolution. In this work, a simple analysis tool is presented which can simulate these phenomena during the co-cure manufacturing of honeycomb sandwich composites. Inputs include material properties of the prepreg, adhesive and the honeycomb core and the specified pressure and temperature cycle. The tool conducts the analysis to provide the output, which includes the degree of prepreg facesheet consolidation, the porosity level at the adhesive bond-line, fillet shape of the adhesive along the core walls and the development of the core pressure. The tool should provide a better understanding of the relationships between the materials, process, and the final bond-line quality, which will result in improvement of the manufacturing process.
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Conference: SAMPE 2019 - Charlotte, NC
Publication Date: 2019/05/20
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