Radio frequency characteristics of carbon fibre composite materials

Abstract

A comprehensive investigation of the r.f. properties of a range of samples of carbon fibre composite materials has been made. These samples were chosen as being representative of those which have been used or are likely to be used in aircraft construction.This paper is in two parts, first the investigations made to determine the electrical resistance characteristics of small samples of CFC materials in the frequency range from d.c. to 300 MHz, and the second part which describes the investigation of the screening performance of larger samples in the frequency range 0.15–30 MHz for the magnetic mode and in the range 50–1000 MHz for the electric mode.The methods of measurement which were developed during the investigation are described in detail together with the experimental results, and the conclusions include some indication of the implications of the installation of CFC panels for e.m.c. problems in aircraft.