Structure dependent properties of carbon nanomaterials enabled fiber sensors for in situ monitoring of composites

Carbon Nanomaterials Based Smart Fabrics with Selectable Characteristics for In-Line Monitoring of High-Performance Composites

“…In stage 1, due to the differences in the microstructures of the various carbon nanomaterial coatings, the level of the resin infiltration to the three types of fiber sensors varies obviously. Because of its fluffy and porous structure, the resin molecules can easily infiltrate and merge into the CNT coating [ 10 ]. The adequate flowing space allows them to be in full contact with the CNTs, causing a huge increase in dR/R0 and improving the upper limit of its growth.…”

“…Following established strategies of materials’ exfoliation [ 28 , 29 ], MWCNTs (300 mg) were sonicated in deionized water (100 mL) with 5 mL of Triton X-100 surfactant for 120 min, using a Ultrasonics FS-600N probe sonicator operated in a pulse mode (on 10 s, off 10 s), with the power fixed at 480 W. Following the same conditions as in the sonication process, the GO dispersion was prepared with 300 mg of GO powders in 100 mL of deionized water. Based on our previous works [ 10 , 26 ], a modified fiber winding and coating system was established, as shown in Figure 1 a, in which the fiber powertrain was made up of a stepping motor and multiple standing pulleys for CNT/GO bathing, aqueous cleaning, and thermal drying. After the coating process, the GO-coated fibers required an additional reduction procedure to form the RGO-coated fibers by dipping the fibers into a hydroiodic acid solution at 85 °C for 30 min.…”

“…Under such circumstances, structural health monitoring (SHM) has emerged as a scientific and necessary tool, playing an important role in identifying, quantifying, and deciding the health states of the high-performance composites. In addition to traditional methods, such as strain gages [ 3 ], optical fibers [ 4 ], metal oxide films [ 5 ], guided waves [ 6 , 7 , 8 ], and piezoelectric sensors [ 9 ], carbon nanomaterials are considered to be novel materials for establishing embeddable, built-in, lightweight, versatile, and flexible self-sensing technology for composites [ 10 ]. Because of their extraordinary mechanical robustness, structural non-invasiveness, and piezoresistive sensitivity [ 11 ], it is important to investigate the great potentiality of novel carbon nanomaterials-based sensors to improve the structural health monitoring performance of composites.…”

Laser‐Induced Freestanding Graphene Papers: A New Route of Scalable Fabrication with Tunable Morphologies and Properties for Multifunctional Devices and Structures

“…coli bacteria was applied by Nikon Eclipse‐Ti‐E microscope. Following the vacuum bagging process introduced previously, smart composites were prepared by embedding a 5 × 5 or 1 × 4 cm 2 LIGP between two layers of prepregs with copper wires connected for resistance monitoring.…”

Real-time strain monitoring and damage detection of composites in different directions of the applied load using a microscale flexible Nylon/Ag strain sensor

“…For example, CNTs based fibers, having high sensitivity, flexibility and outstanding impact resistance, were used in real-time damage monitoring of composites [43,44]. But their sensitivity was affected when inserted into the composite specimens because of the two reasons, one tunneling effect and other is the porous network of CNTs which is permeable to resin molecules [45][46][47][48]. Fibers coated with reduced graphene oxide (RGO) didn't have resin penetration because of their geometry and surface conformability and showed high sensitivity, flexibility, and stability in real-time monitoring of high strain applications [49].…”