Mechanical properties of Nomex honeycombs filled with tubes of carbon fibre reinforced vinyl ester resin composites

Abstract

The Nomex honeycomb structures filled with carbon fibre reinforced vinyl ester resin composite tubes (NHFCT) were proposed to improve the energy absorption capacity of Nomex honeycombs. Thereafter, the mechanical properties of the NHFCT structures were explored based on the quasi-static pressure test, finite element simulation, and a theoretical model. The test result showed that the NHFCT structures enable increased SEA while retaining the energy absorption performance of Nomex honeycombs. When applying a certain load on the NHFCT structures, the Nomex honeycombs are folded; the CFRP tubes are torn and expanded, and the embedded cells bulge. The established finite element simulation model was used to simulate the deformation of NHFCT structures and the theoretical model was employed to predict their energy absorption performance. Tests applicable to the practical application revealed that NHFCT structures of a large area present more stable performance and the superimposed NHFCT structures are subjected to step-wise gradient deformation. The CFRP tubes suffer slight indentation on the panel between layers and they are torn in a funnel shape under the effect of the panel stiffness. The research provides reference for improving the mechanical properties of Nomex honeycomb structures and broadening their range of application.