Interfacial engineering of Y ₂ O ₃ -modified adhesive layers for tunable impact energy dissipation and damage control in titanium/carbon-basalt fibre metal laminates

This study presents an experimental – analytical investigation on the role of Y2O3-reinforced adhesive layers in governing the low-velocity impact response of titanium/carbon – basalt hybrid fibre metal laminates. A three-factor framework comprising impact mass (2–6 kg), velocity (2.5–7.5 m/s), and Y2O3 content (0–2 wt.%) was employed to establish process – structure – performance relationships. Impact responses were evaluated in terms of peak force, deformation, contact time, energy absorption, impulse, and velocity attenuation. Results indicate that impact mass is the dominant parameter, contributing up to 87.77% to peak force and 82.67% to energy absorption, reaching ~10107 N and ~38.21 J, respectively. In contrast, Y2O3 content significantly governs interfacial behaviour, contributing ~75.85% to contact time and ~32.51% to impulse, highlighting its role in energy dissipation and load transfer. Y2O3 incorporation enhances interfacial stiffness, promotes crack deflection, and limits damage propagation. Damage analysis shows a transition from localized indentation (~13.20 mm2) to severe material removal (~70.88 mm2), with optimized conditions exhibiting confined deformation. Statistical models demonstrate high accuracy (R2 >94%), and multi-response optimization identifies 2 wt.% Y2O3 as optimal for balanced impact performance.