Design of eddy current-based dielectric constant meter for defect detection in glass fiber reinforced plastics. (September 2015)

• Record Type: Journal Article
• Authors: Mizukami, Koichi; Mizutani, Yoshihiro; Todoroki, Akira; Suzuki, Yoshiro
• Is Part Of: NDT & E international. Volume 74(2015:Sep.)
• Page Start: 24
• Page End: 32
• Publication Date: 2015-09
• Subjects: Composite materials -- FRP (fiber reinforced) plastic -- Dielectric -- Eddy currents -- Theoretical modeling; Nondestructive testing -- Periodicals; Contrôle non destructif -- Périodiques; Electronic journals; 620.1127
• DOI: 10.1016/j.ndteint.2015.04.005
• Languages: English
• ISSNs: 0963-8695

Abstract

Abstract: This paper presents the design of an eddy current testing probe for inspection of non-conductive glass fiber reinforced plastics. Because the magnetic field contains information pertaining to the permittivity of materials under test, eddy current testing offers the possibility of flaw detection in non-conductive materials through detection of the difference in permittivity between the intact part and the defective part of each material. We analytically investigated the design of a probe suitable for dielectric constant measurements. Experimental studies proved that the proposed probe can detect slit defects and flat-bottomed holes located 2 mm away from the surface of the glass fiber reinforced plastic samples. Highlights: Influence of permittivity of tested sample on ET signal was analytically derived. Design of ET probe for permittivity sensing was investigated. Probe dimensions affect displacement current distribution. Slit defect and flat bottomed holes 2 mm from surface were detected by the probe.