Evaluation of the Characteristics of Electromagnetic Waves of CFRTP for Multimedia Instrument Applications. 2nd Report. Effects of Compressive and Impact Damage on Shielding Effectiveness of Carbon Fiber-Reinforced Thermo Plastics against an Electromagnetic Wave.

Abstract

The need for plastic composites increases with the increasing use of electronic instruments such as robots, personal computers and cellular phones come into wider use. Carbon fiber-reinforced thermoplastic, CFRTP, is one plastic composite used for electronic instruments. It is favored as a casing for multimedia instruments because it has good deformation and recycling capabilities. It is important to study the shielding effectiveness, SE, of CFRTP against electromagnetic radiation. In the present paper, the shielding effectiveness was experimentally investigated in an electronic shielding room for the CFRTP of which the resin materials were varied in PC, PP, PEI, PMMA and PA. The effects of compressive and impact damage on the shielding effectiveness were studied when the carbon fiber orientation and the space between fiber bundles were changed. The shielding effectiveness strongly depended on the orientation of the carbon fiber. It also decreased when the space between the fiber bundles was increased but was scarcely influenced by the resin materials. When the CFRTP formed a compressive trace on the plate surface by compressive load, the shielding effectiveness increased when the compressive load was increased, and thus depended on the shape of compressive trace.