Fuse-like devices replacing linear sensors—working examples of percolation sensors in operational airliners and chemical installations

Pfeiffer, Helge; Pitropakis, Ioannis; Wevers, Martine; Sekler, Hans; Schoonacker, Marc

doi:10.1201/b19381-37

Cited by 1 publication

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In contrast, above M t,c , the very same specimens exhibit a stronger sensitivity to water uptake ( S 2 ) assessed between 5.57 and 116 MΩ/% water . A nonlinear resistive response associated with a strong sensitivity would allow some independence of operation-dependent baseline variations compared to many humidity sensors that frequently operate in a linear or quasi-linear mode . Thus, if the water uptake in near-EPT CB-epoxy nanocomposites exceeds the threshold M t,c , the probability of detecting water is maximal.…”

Section: Resultsmentioning

confidence: 99%

Effects of Water Uptake on the Electrical Properties of Carbon Black-Epoxy Nanocomposites

Fauche,

Windey,

Pfeiffer

et al. 2024

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

Water ingress in composite structures is a potentially costly problem, and its detection before related damage begins to appear is of utmost importance. Carbon black fillers (CB) and epoxy matrices can be used to produce water-sensitive nanocomposites that can be integrated into composites during production. Nevertheless, the effects of water uptake on the electrical properties of CB-epoxy nanocomposites have scarcely been reported. Therefore, this paper successfully provides a better understanding of the resistance-water uptake response of such a material. Bulk specimens were manufactured and then characterized by bulk resistivity measurements and broadband dielectric spectroscopy (BDS) to determine the electrical percolation threshold (EPT). The former technique yielded an EPT at 1.71 ± 0.08 wt %CB, which is in good agreement with the EPT range (1.82−1.90 wt %CB) assessed by BDS at 1 Hz (equivalent to DC conditions). Among the Fickian, Langmuir, and relaxation-based model (PEK), the latter best describes the water diffusion kinetics for three immersed specimens with a filler loading near (1.30 and 2.00 wt %CB) and beyond (3.00 wt %CB) the EPT. Both the resistance and absolute impedance (<10 kHz) show a quasi-linear increase induced by water uptake. The change in relative resistance as a function of the water uptake revealed a pseudo-nonlinear piezoresistive behavior. This behavior was particularly significant once the water uptake in near-EPT specimens exceeded a certain threshold, related to a saturation of at least 60%. Above this threshold, the near-EPT specimens showed a strong sensitivity to water uptake, estimated between 5.57 and 116 MΩ/% water . Thus, the near-EPT CB-epoxy nanocomposites were demonstrated to have great potential to detect the ingress of water into the composite structures.

show abstract

Section: Resultsmentioning

confidence: 99%