Role of Nanofillers in Improving Delamination Resistance of Laminated Composites

Abstract

Laminated composites, widely used in aerospace, automotive, and marine applications, 
are susceptible to delamination, a primary failure mode that compromises structural integrity. 
Nanofillers such as carbon nanotubes (CNTs), graphene nanoplatelets (GNPs), carbon nanofibers 
(CNFs), and nanoclays have been extensively investigated for enhancing interlaminar properties 
and delamination resistance. This review synthesizes recent studies on the incorporation of 
nanofillers into epoxy-based fiber-reinforced polymers (FRPs), focusing on mechanisms like crack 
bridging, pull-out, and deflection. Experimental and modeling approaches reveal improvements in 
mode I and II fracture toughness (G_Ic and G_IIc) by 30-140%, fatigue life extensions up to 
fivefold, and reductions in delamination areas by 20-50%. Functionalization and optimal loadings 
(0.1-4 wt.%) are critical to avoid agglomeration. Hybrid multi-scale reinforcements show 
synergistic effects, particularly in carbon fiber/epoxy systems. Challenges include dispersion 
uniformity and rate-dependent behavior, with future directions emphasizing multiscale modeling 
and environmental durability assessments. This paper provides insights for designing damage
tolerant composites.