Fracture toughness and failure mechanism of graphene based epoxy composites

Enthalten in
Composites science and technology 
Volume
97
Start Page
90
End Page
99
Citation
Composites Science and Technology 97 (): 90-99 (2014-06-16)
Publisher DOI
10.1016/j.compscitech.2014.03.014
Scopus ID
2-s2.0-84899805405
Publisher
Elsevier
The present study investigates the effect of addition of three different types on carbon nano-fillers on fracture toughness (KIC) and failure mechanism of epoxy based polymer nano-composites. The carbon nano-fillers were dispersed in the epoxy matrix using a three-roll mill and the three nano-fillers used for this experiment were (i) thermally reduced graphene oxide (TRGO); (ii) graphite nano-platelets (GNP); and (iii) multi-wall carbon nano-tubes (MWCNT). The fracture toughness was measured as a function of weight percentage of the filler using single edge notch three-point-bending tests. The toughening effect of TRGO was most significant resulting in 40% increase in KIC for 0.5wt% of filler. On the other hand, the enhancements in toughness were 25% for GNP/epoxy and 8% for MWCNT/epoxy. Investigations on fracture surface revealed that crack pinning or bi-furcation by TRGO and crack face separation initiated from TRGO contributed to enhance the fracture toughness. Based on the observations, a schematic explaining the crack propagation in graphene/epoxy composite and the interaction of crack front with graphene particles was proposed.
Schlagworte
A. Nano-composites
B. Fracture
B. Fracture toughness
D. Fractography
D. Scanning electron microscopy
DDC Class
600: Technik
More Funding Information
The authors would like to acknowledge Mr. Varun Gopal student assistant, for his support in sample production. We would also like to acknowledge DAAD-SIEMENS A/10/71620 scholarship for the financial support.