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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 6 J energy (a) amplitude; (b) phase.
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sensors-15-15903-f009: The measured signal delivered by the electromagnetic sensors with MM lens at scanning of composite FRPC quasi-isoptropic in plane samples impacted with 6 J energy (a) amplitude; (b) phase.

Mentions: From the mechanics of composite materials it is known that due to an impact normal to the surface of the composite, delaminations can appear, whose shapes are approximately concave, a fact visible in Figure 9a. Therefore, the area of the delaminated surface can be determined, making the method effective for the examination of FRPC. In Figure 9a,b we show the information regarding the amplitude and phase for the signal induced in the reception coil of the sensor by the scanning of a region 60 × 60 mm2 of the composite, which contains a delamination following an impact of 6 J energy. On the border of the electromagnetic image, the structure of the woven fabric can be observed, while in the central zone, the delaminated region is emphasized.


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 6 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-f009: The measured signal delivered by the electromagnetic sensors with MM lens at scanning of composite FRPC quasi-isoptropic in plane samples impacted with 6 J energy (a) amplitude; (b) phase.
Mentions: From the mechanics of composite materials it is known that due to an impact normal to the surface of the composite, delaminations can appear, whose shapes are approximately concave, a fact visible in Figure 9a. Therefore, the area of the delaminated surface can be determined, making the method effective for the examination of FRPC. In Figure 9a,b we show the information regarding the amplitude and phase for the signal induced in the reception coil of the sensor by the scanning of a region 60 × 60 mm2 of the composite, which contains a delamination following an impact of 6 J energy. On the border of the electromagnetic image, the structure of the woven fabric can be observed, while in the central zone, the delaminated region is emphasized.

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