University of Cambridge
Using 3D Printing to Improve the Impact Resistance of Sandwich Panels
Abstract
dc:description.abstractSandwich panels are a stiff, yet lightweight structure commonly found in aerospace applications. However, their low density cores can limit their performance in strength and impact resistance. Advances in 3D printing have created the potential to use new materials and create new geometries for sandwich panel cores to improve their impact resistance. A uniform-density honeycomb core made from ULTEM-1010 was designed. It was then tested in quasi-static compression, bending and indentation, low-velocity impact and high-velocity impact regimes and then compared against two typical reference designs. The 3D printed ULTEM-1010 panel design showed a significant improvement in core compressive strength and indentation energy absorption in all testing regimes. However, it suffered from less bending stiffness compared to the reference panel designs. The ULTEM-1010 panel showed an increase in perforation energy during high-velocity impact when compared to quasi-static indentation. Through-thickness variation was introduced into the ULTEM-1010 core designs to improve the weaker bending performance of the 3D printed core. One graded design provided a small improvement in bending stiffness and perforation energy during quasi-static indentation. However, the introduction of additional failure modes meant that these improvements did not translate up to higher strain rates. A high-resolution FE model was developed to predict the evolution of damage within each panel, to help support interpretation of the experiments and to aid the design process for 3D printed cores. A particular challenge of modelling the behaviour of the 3D printed polymer is its quasi-brittle nature. A novel approach for modelling this quasi-brittle behaviour was tested. This was found to provide a good match with experiments. Overall, the new 3D printed core designs, designed using a combination of experiment, analytical and numerical modelling, met their objective in improving indentation resistance and impact damage tolerance. Furthermore, they showed potential for further development and several areas were identified with scope for further performance improvements.
Degree
thesis:*- Name dc:type.qualificationname
- Doctor of Philosophy (PhD)
- Level dc:type.qualificationlevel
- Doctoral
- Grantor dc:publisher.institution
- University of Cambridge
- Year dc:date.issued
- 2025
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Stevens, Peter
- Advisor dc:contributor.advisor
-
- McShane, Graham
Subjects
dc:subject × 6Rights
dc:rightsIdentifiers
dc:identifier.*- DOI dc:identifier.doi
- https://doi.org/10.17863/CAM.127477
- OAI identifier oai:identifier
- oai:www.repository.cam.ac.uk:1810/398665