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An Electromagnetic Sensor with a Metamaterial Lens for Nondestructive Evaluation of Composite Materials.

Savin A, Steigmann R, Bruma A, Šturm R - Sensors (Basel) (2015)

Bottom Line: These structures can serve as electromagnetic flux concentrators in the radiofrequency range.The evaluation method is based on the appearance of evanescent modes in the space between carbon fibers when the sample is excited with a transversal magnetic along z axis (TMz) polarized electromagnetic field.The flaws can be localized with spatial resolution better than λ/2000.

View Article: PubMed Central - PubMed

Affiliation: Nondestructive Testing Department, National Institute of R&D for Technical Physics, 47 D. Mangeron Blvd, 700050 Iasi, Romania. asavin@phys-iasi.ro.

ABSTRACT
This paper proposes the study and implementation of a sensor with a metamaterial (MM) lens in electromagnetic nondestructive evaluation (eNDE). Thus, the use of a new type of MM, named Conical Swiss Rolls (CSR) has been proposed. These structures can serve as electromagnetic flux concentrators in the radiofrequency range. As a direct application, plates of composite materials with carbon fibers woven as reinforcement and polyphenylene sulphide as matrix with delaminations due to low energy impacts were examined. The evaluation method is based on the appearance of evanescent modes in the space between carbon fibers when the sample is excited with a transversal magnetic along z axis (TMz) polarized electromagnetic field. The MM lens allows the transmission and intensification of evanescent waves. The characteristics of carbon fibers woven structure became visible and delaminations are clearly emphasized. The flaws can be localized with spatial resolution better than λ/2000.

No MeSH data available.


Related in: MedlinePlus

The measured signal delivered by the electromagnetic sensors with MM lens at scanning of composite FRPC quasi-isoptropic in plane samples impacted with 8 J, 10 J and 12 J energy (a) amplitude; (b) phase.
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sensors-15-15903-f010: The measured signal delivered by the electromagnetic sensors with MM lens at scanning of composite FRPC quasi-isoptropic in plane samples impacted with 8 J, 10 J and 12 J energy (a) amplitude; (b) phase.

Mentions: Figure 10 presents the signal given by the same sensor at the scanning of a region of composite which contains a delamination due to 8 J, 10 J and 12 J energy impact. Examining Figure 9 and Figure 10, it can be observed that for impacts with energies equal to 6 J and higher, the energy absorbed by the composite increases with the increasing impact energy, so the area of delamination increases in the same manner. It is visible that plastic deformations appear in the region of impact that lead to an increasing electrical conductivity of the area. Fibers in electrical contact, debonding of fibers from matrix can appear as consequences of the mechanical strength of the structures made from this composite.


An Electromagnetic Sensor with a Metamaterial Lens for Nondestructive Evaluation of Composite Materials.

Savin A, Steigmann R, Bruma A, Šturm R - Sensors (Basel) (2015)

The measured signal delivered by the electromagnetic sensors with MM lens at scanning of composite FRPC quasi-isoptropic in plane samples impacted with 8 J, 10 J and 12 J energy (a) amplitude; (b) phase.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541860&req=5

sensors-15-15903-f010: The measured signal delivered by the electromagnetic sensors with MM lens at scanning of composite FRPC quasi-isoptropic in plane samples impacted with 8 J, 10 J and 12 J energy (a) amplitude; (b) phase.
Mentions: Figure 10 presents the signal given by the same sensor at the scanning of a region of composite which contains a delamination due to 8 J, 10 J and 12 J energy impact. Examining Figure 9 and Figure 10, it can be observed that for impacts with energies equal to 6 J and higher, the energy absorbed by the composite increases with the increasing impact energy, so the area of delamination increases in the same manner. It is visible that plastic deformations appear in the region of impact that lead to an increasing electrical conductivity of the area. Fibers in electrical contact, debonding of fibers from matrix can appear as consequences of the mechanical strength of the structures made from this composite.

Bottom Line: These structures can serve as electromagnetic flux concentrators in the radiofrequency range.The evaluation method is based on the appearance of evanescent modes in the space between carbon fibers when the sample is excited with a transversal magnetic along z axis (TMz) polarized electromagnetic field.The flaws can be localized with spatial resolution better than λ/2000.

View Article: PubMed Central - PubMed

Affiliation: Nondestructive Testing Department, National Institute of R&D for Technical Physics, 47 D. Mangeron Blvd, 700050 Iasi, Romania. asavin@phys-iasi.ro.

ABSTRACT
This paper proposes the study and implementation of a sensor with a metamaterial (MM) lens in electromagnetic nondestructive evaluation (eNDE). Thus, the use of a new type of MM, named Conical Swiss Rolls (CSR) has been proposed. These structures can serve as electromagnetic flux concentrators in the radiofrequency range. As a direct application, plates of composite materials with carbon fibers woven as reinforcement and polyphenylene sulphide as matrix with delaminations due to low energy impacts were examined. The evaluation method is based on the appearance of evanescent modes in the space between carbon fibers when the sample is excited with a transversal magnetic along z axis (TMz) polarized electromagnetic field. The MM lens allows the transmission and intensification of evanescent waves. The characteristics of carbon fibers woven structure became visible and delaminations are clearly emphasized. The flaws can be localized with spatial resolution better than λ/2000.

No MeSH data available.


Related in: MedlinePlus