Deformation behaviour of re-entrant carbon honeycomb structures

Abstract

Recent successes of researchers in the fabrication of new carbon structures of different morphologies and dimensions open up broad prospects for the development of carbon materials with qualitatively new properties. Such promising materials are cellular structures (or carbon aerogels) that have high deformability, good adsorption and conductivity characteristics. In this work, we consider a carbon structure consisting of re-entrant honeycomb cells, which allow the structure to be auxetic. The stability and deformation behaviour of re-entrant carbon honeycomb structures is studied by molecular dynamics simulation. The effect of structural parameters on the stability of carbon aerogel is discussed. It is shown that structural changes significantly depend on the strain rate and the loading direction. At a high strain rate in tension along the z-axis, all cells open slightly at the same time. On the contrary, at small strain rates, certain cells open, while others almost completely collapse, which is expected to result in changes in physical properties, for example, in conductivity. During tension along the x-axis, a transformation from a re-entrant honeycomb to a traditional honeycomb took place.