Title: Modelling of Core Crush Phenomenon during the Processing of Honeycomb Sandwich Panels

Authors: Sanesh Iyer, Lucie Riffard, Tara Baker, Marta Elleby, Pascal Hubert

DOI: 10.33599/nasampe/s.21.0574

Abstract: Autoclave co-curing of carbon-fibre prepregs and Nomex honeycomb sandwich structures reduces the number of manufacturing apparatus and time required, presenting clear cost advantages. However, the application of pressure and viscous nature of prepregs can cause motion of the core during processing, leading to scrapped parts. In this work, a finite element model which predicts the occurrence of core-crush is developed and used to study the effect of various processing and geometric parameters on the core crush phenomenon. The effects of prepreg curing are considered in the development of this finite element. The friction behaviour of prepregs as well as the in-plane elastic and plastic properties of honeycomb cores are measured experimentally. The permeability of prepreg is measured experimentally to determine pressure inside the core during cure. The finite element model is validated against experimental data and is shown to accurately predict the onset of core crush for 81% of evaluated cases. The material contained in this paper is based upon work supported by NASA under award No. NNL09AA00A and 80LARC17C0004.

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Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000574

Pages: 17

Price: FREE