Аннотация
Adhesive joints attract implementation in structural systems whose integrity depends on the strength and durability of bonded joints. Nanofillers are employed to reinforce adhesive joints for longer service life. This study investigates mechanical performance and failure mechanism of polyurethane (PU)/α-zirconium phosphate (α-ZrP) nanocomposite adhesives using integrated finite element (FEM) and discrete element modelling (DEM) frameworks, validated against experimental measurements on aluminium-aluminium (Al-Al) single lap joints (SLJs) bonded with PU adhesive. FEM incorporates viscoelastic behaviour and cohesive zone formulation to predict stress-strain and load-displacement responses of PU/α-ZrP nanocomposite and Al-Al/PU SLJs. Sensitivity analysis of tensile strength simulations defined Poisson’s ratios of neat PU and 0.5 wt% PU/α-ZrP nanocomposite. Stress analysis of SLJs reveals pronounced peak stresses at overlap edges due to load-path eccentricity and adherend bending, while compressive stresses develop in the central bondline. Scalar stiffness degradation indicates neat PU exhibits distributed cohesive damage across ∼52% of the cohesive layer at 94% of maximum load. In contrast, α-ZrP-reinforced system confines damage to overlap edges, with only 13.8% of the bondline exceeding 90% damage; this indicates improved structural stability. DEM simulations using Johnson-Kendall-Roberts (JKR) cohesive model provided microscale insight into bond coordination and degradation, yielding particle-particle cohesion energy densities of 4 J/m 2 and 5 J/m 2 for neat PU and 0.5 wt% α-ZrP-reinforced PU, respectively. The reinforced system demonstrated reduced bond depletion and more stable contact evolution than neat PU. Experimental tensile and SLJ tests validated both FEM and DEM, demonstrating that integrated FEM-DEM enables multi-scale characterization of adhesive joint performance.