Title :
Dielectric spectroscopy of fiber-reinforced epoxy materials
Author :
Krivda, A. ; Page, S.A. ; Meier, G. ; Wright, S.
Author_Institution :
Corp. Res., ABB Switzerland Ltd., Baden, Switzerland
Abstract :
In this paper dielectric spectroscopy measurements on four different fiber-reinforced epoxy materials are presented. The results show that the dielectric constant and tan δ of glass, quartz, aramid (Kevlar) and poly-benzobisoxazole (Zylon) fiber-reinforced epoxy materials are in the range similar to the other commonly used insulating materials. Long-term thermal cycling from -40°C to 120°C during a period of 2500 hours has not affected the values of dielectric constant and tan δ. Surface treatment of fibers plays an important role in the values of dielectric constant and tan δ. With certain types of surface treatment unacceptable values of the dielectric constant (about 50) and tan δ (about 0.3) were obtained. The quality of fiber-reinforced materials was verified by optical and scanning electron microscopy. Neither voids nor delaminations were detected.
Keywords :
delamination; epoxy insulation; fibre reinforced composites; glass; optical microscopy; permittivity; quartz; scanning electron microscopy; surface treatment; voids (solid); -40 to 120 degC; 2500 hour; Kevlar; Zylon; aramid; delaminations; dielectric constant; dielectric spectroscopy; fiber-reinforced epoxy materials; glass; insulating materials; long-term thermal cycling; optical; poly-benzobisoxazole; quartz; scanning electron microscopy; surface treatment; voids; Dielectric constant; Dielectric materials; Dielectric measurements; Dielectrics and electrical insulation; Electrochemical impedance spectroscopy; Electron optics; Glass; Optical materials; Optical microscopy; Surface treatment;
Conference_Titel :
Solid Dielectrics, 2004. ICSD 2004. Proceedings of the 2004 IEEE International Conference on
Print_ISBN :
0-7803-8348-6
DOI :
10.1109/ICSD.2004.1350393
