Impact sensing, localization and damage assessment in Fiber-Reinforced composites with ZnO Nanowires-Based sensor array

In this work, zinc oxide nanowires (ZnO NWs) were embedded into a carbon fiberreinforced composite serving as mechanical reinforcement and sensing components. The introduction of ZnO NWs not only enhanced the bonding at the fiber/resin interface but also created a mechanical interlocking effect, addressing the common issue of embedded sensing approaches reducing the integrity of the host composite material. For laminate subjected to external loads, the piezoelectric properties of ZnO NWs generated separated charges, leading to increased sensitivity of capacitive monitoring. The monitoring load distribution was achieved by monitoring the change ratio in the array capacitance on the laminate. An algorithm was also proposed to calculate the array capacitive change ratio, achieving precise localization, and quantification of the impact load, with localizing error and quantifying error within 3 mm and 0.25 MPa, respectively. Multi-point static load distribution and the tracking of the entire process of dynamic loads can be identified. Additionally, monitoring changes in initial capacitance allowed effectively determining the integrity of the composite material after an impact load. In sum, the proposed embedded sensing method based on ZnO NWs offers high precision and minimal aggressiveness, promising for applications in the field of structural health monitoring. [Display omitted] •Composites with enhanced mechanical properties enable precise impact load localization and quantification.•The embedded ZnO NWs serve as mechanical reinforcement and sensing components.•Enhanced mechanical properties result from strong bonding at the fiber/resin interface and mechanical interlocking effect.•Multisensory capabilities include static load monitoring, precise localization, dynamic load tracking, and damage evaluation. The structural integrity and monitoring of load distributions in composites are critical for safety and economic efficiency but still challenging. Herein, zinc oxide nanowires (ZnO NWs) were embedded into a carbon fiber-reinforced composite serving as mechanical reinforcement and sensing components. The presence of ZnO NWs in the composite material increased the flexural strength, interlaminar, and interfacial shear strength by respectively 4.9 %, 8.8 %, and 19.9 % due to the strong bonding at the fiber/resin interface and the mechanical interlocking effect. Additionally, the piezoelectric nature of ZnO NWs with an asymmetric crystal structure generated pie