Title: Printable Epoxy Core for Hybrid Manufacturing of Composite Sandwich Structures

Authors: Andrew C. Abbott, Gyaneshwar P. Tandon, Hilmar Koerner, and Jeffery W. Baur

DOI: 10.33599/nasampe/c.19.0723

Abstract: Composite sandwich structure cores are used for weight reduction without sacrificing stiffness, but their design is not engineered to optimize performance under given in-service loading conditions. In order to realize optimal performance, an engineer needs customizability, geometric complexity, and manufacturing process flexibility – all attributes of additive manufacturing. Another benefit of additive manufacturing is the potential to reduce the number of sandwich composite manufacturing steps by printing a core directly onto prepreg preforms with a material of similar chemistry and co-curing the structure. To this end, honeycomb cores are printed with a chopped fiber reinforced epoxy ink onto carbon fiber epoxy prepreg. As a comparison, sandwich composites are also fabricated by adhesively bonding printed and cured honeycombs onto composite laminates and tested in 3-point flexure. Progress and challenges with these processes are discussed.

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Conference: CAMX 2019

Publication Date: 2019/09/23

SKU: TP19-0723

Pages: 12

Price: $24.00