The mechanical response of glassy carbon recovered from high pressure

Abstract

Glassy carbon (GC) is usually considered the prototypical super-elastic material, which can almost fully recover its shape after compression of several gigapascals (GPa). In this work, nanoindentation is used to study the mechanical response of GC, which was subjected to a range of high pressures using a diamond anvil cell (DAC). We show that GC starts to lose its elasticity after compression to 6 GPa and becomes clearly mechanically anisotropic after being compressed beyond ∼30 GPa. Molecular dynamics (MD) simulations are used to calculate Young's modulus before and after compression. Through our experimental results and MD simulations, we show that the elasticity of GC is at a minimum around 30 GPa but recovers after compression to higher pressures along the DAC compression axis.

Molecular dynamics approach for predicting release temperatures of noble gases in pre-solar nanodiamonds

“…All three of these pre-solar materials have high melting points and therefore are suitable for our Arrhenius-based approach. While we are unware of any study of noble gas incorporation in these pre-solar materials, there are a number of successful atomistic simulation studies of high-temperature effects in silicon-carbide [55], graphite and carbide-derived-carbons [30,31] and glassy carbon [26,27,56]. These structures provide a natural starting point for further atomistic simulations to reveal the astrophysical secrets of noble gases in pre-solar grains.…”

Direct Measurement of the Transverse Modulus of Carbon Fibres

“…However, the change in E T after plasticity may vary between samples and may not be as distinct as was observed in the HS40 CF. Indentation studies have previously proposed the consideration of energy-based metrics for the analysis of elasto-plastic deformations [37], which have been applied to hysteretic materials [36,38] via the defining of a ductility index (D) such that:…”