Quasi-static compressive strength of polymethacrylimide foam-filled square carbon fiber reinforced composite honeycombs

Abstract

A novel polymethacrylimide foam-filled square carbon fiber reinforced composite honeycomb core was proposed and prepared. Numerical simulations and theoretical predictions were conducted to study the quasi-static compressive strength of the hybrid core. The effects of material and structural parameters on the compressive strength of the core were analyzed. The results show that the failure modes of the core under quasi-static compression include elastic buckling and plastic fracture failure. The change law of the compressive strength of the core with the increase in the relative density can be divided into three phases, including post-buckling load bearing stage, buckling failure stage, and fracture stage. The failure modes of the core and the change law of the compressive strength with the increase of the relative density vary with the material and structural parameters. The research provides an accurate method to predict the compressive strength of the foam-filled composite honeycomb, which can help to guide the design and optimization of light weight and energy-efficient sandwich cores.