The Measurement with Respect to Statical Characteristics, of Fiberglass Reinforced Plastics (FRP) by the Light Transmission Method

Abstract

In recent years active researches have been made of nondestructive testing of Fiberglass Reinforced Plastics (FRP), and the following methods have so far been employed for the purpose.(1) The use of X-Rays(2) The use of Ultrasonic Waves(3) The utilization of Temperature(4) The transmission of Light Waves (Infra-Red Rays)(5) KnockOf these the X-ray and the ultrasonic wave methods have been found as respectively useful, and the light wave method, though its practical application has been but little known, has been found as equipped with the following advantages.(1) That it requires simple apparatuses.(2) That it is of easy procedure.(3) That it permits good transmission.These advantages will recommend the light wave method to recognition as most suitable in our present experiment. That was the way the light wave method was adopted for the nondestructive besting of FRP, and the results of its measurements with respect to its strain, glassfiber direction and the number of layers are reported hereunder.The diffraction patterns that were recorded as they took place under stress were given out as the strain of the FRP. The light wave transmission method has given due to the glassfiber direction in the FRP and to the number of its layers by making the light pass through the material. The light wave transmission method is thus confirmed by these results of the experiment as an effective device for nondestructive testing of FRP.