Study on the synergistic effect of carbon nanofillers on the interlaminar toughness of fibre metal laminates

Delamination failure is the main damage mode of fibre metal laminates (FMLs), including the combination of aluminium alloy and glass fibre reinforced epoxy. The present study focuses on the mode I interlaminar fracture toughness of FMLs with dispersion and synergy in resin matrix of two different carbon nanofillers, layered Graphenes (GNPs) and Multi-Walled Carbon Nanotubes (MWCNTs). The double cantilever beam (DCB) was implemented to test the mode I strain energy release rate (GCYRILLIC CAPITAL LETTER BYELORUSSIAN-UKRAINIAN IC) of FMLs with a fixed content (1 wt%) of GNPs, MWCNTs and GNPs/MWCNTs at 1:1. The addition of carbon nanofillers has positive effect on the interlaminar performance of FMLs. The initial strain energy release rate (GCYRILLIC CAPITAL LETTER BYELORUSSIAN-UKRAINIAN IC, ini) values of FMLs with GNPs and MWCNTs are 0.369 and 0.475 KJ/m2, which represent increases of 8.87 % and 40.1 %, respectively. The maximum GCYRILLIC CAPITAL LETTER BYELORUSSIAN-UKRAINIAN IC, ini value of GNPs/MWCNTs modified FMLs is 0.672 KJ/m2, which represents a 98.2 % increase. Scanning Electron Microscopy (SEM) reveals the mechanism of hybrid toughening. During the mode I crack propagation process, the synergistic effect of the two nanofillers is more useful in the interlaminar fracture toughness.

Automated summary

In this study, the interlaminar fracture toughness of FMLs with two different carbon nanofillers was investigated, revealing that the addition of carbon nanofillers has a positive effect on the interlaminar performance of FMLs, with the GNPs/MWCNTs hybrid filler showing the best results.