Nano indentation Based Fracture Characterization of Multiphase Nanocomposites

Abstract

Multiphase nanocomposites, comprising multiple types of nanoscale reinforcements within a polymer or metallic matrix, exhibit superior mechanical properties including enhanced stiffness, strength, and fracture toughness. Understanding fracture behavior in these complex materials requires high-resolution techniques capable of probing local mechanical responses. Nanoindentation provides a powerful method to assess mechanical properties and fracture characteristics at the microscale, enabling direct measurement of hardness, modulus, and crack propagation phenomena. This paper investigates the fracture behavior of multiphase nanocomposites using nanoindentation-based methods, integrating experimental testing, microscopic analysis, and computational modeling. Various combinations of carbon nanotubes (CNTs), graphene nanoplatelets (GNPs), and silica nanoparticles were embedded in polymer matrices to evaluate their synergistic effect on crack resistance and energy dissipation. Results indicate that nanoindentation effectively captures localized fracture initiation, propagation, and toughening mechanisms such as crack bridging, particle pull-out, and matrix plasticization. These insights facilitate the design of multiphase nanocomposites with optimized fracture performance for applications in aerospace, electronics, and protective coatings.