Design of Carbon Nanotube Sheet Embedded Fiber Composites with In Situ Structural Health Monitoring Capability

摘要

Damage accumulation in fiber composites is complex and incipient damage isdifficult to detect using conventional non-destructive evaluation techniques. Differentdamage modes ranging from micro-level to macro-level (fiber breakage, micro andtransverse matrix cracks development, fiber-matrix de-bonding, delamination, etc.), willaffect the structural performance and durability of the materials. There is an emergingneed for smart composite materials with self-damage sensing capabilities to increase thereliability of composite materials. Recently, advances in macroscopic forms of carbonnanotube materials provide the potential for structural health monitoring using carbonnanotube sheets integrated in the interlaminar areas of advanced fiber composites. Thisresearch explores the fabrication of fiber composites with laminated carbon nanotubesheets embedded for strain sensing and damage detection based on the spatial electricalproperty changes of the carbon nanotube sheets. The mechanical-electrical responsebehavior is recorded under multiple loading conditions, including quasi-static andimpact loading, and the data are analyzed to determine the sensing ability. Themanufacturing process of integrating the carbon nanotube sheets into the systemstrongly affects the sensitivity and repeatability of the integrated multifunctionalsensors. The ultimate goal of this research is to develop reliable structural healthmonitoring methods capable of obtaining information on the damage state in real-time.