Failure mechanisms, electrical and thermal conductivity of Aerographite/epoxy composite

Link:
Autor/in:
Verlag/Körperschaft:
Hamburg University of Technology
Erscheinungsjahr:
2015
Medientyp:
Text
Schlagworte:
  • 3D graphene network
  • Electrical conductivity
  • Failure mechanisms
  • 600: Technik
Beschreibung:
  • Aerographite (AG) is a novel hierarchical carbon nanomaterial formed by a 3D-network of directly interconnected thin-walled graphite layers with densities in rage of 0.2-15 mg/cm3 [1]. AG is synthesized using a single-step CVD process on ZnO templates where simultaneous deposition of graphitic layers and etching of Zn takes place. Despite the ultra-low density, Aerographite's unique morphology consisting of tubular, interconnected graphitic hollow tetrapods enables infiltration with a polymeric matrix. Aerographite/epoxy nanocomposites have been prepared using a novel, proprietary vacuum assisted infiltration technique. The density and the electrical conductivity of the neat AG used for the preparation of the composite is ~12 mg/cm3 and 2-3 S/m respectively. Optical investigations confirm that the 3D interconnected structure remains in-tact during the infiltration process. The composite after infiltration with epoxy was characterized for its electrical and mechanical properties. The electrical conductivity of AG/composite was 7-8 S/m for 0.85-0.88 wt% of AG content. Preliminary results on fracture toughness (KIC) showed an enhancement of 19 % in KIC for AG/epoxy composite with 0.45 wt% of AG. Observations of fractured surfaces under scanning electron microscope gives evidence of pull-out of arms of AG tetrapod, interface and inter-graphite failure as the dominating mechanism for the toughness improvement in these composites. Evidence of increased energy absorption were observed through compression tests and via interaction of crack front with an AG network through photoelasticity experiments.
Quellsystem:
TUHH Open Research

Interne Metadaten
Quelldatensatz
oai:tore.tuhh.de:11420/6499