抄録
By using Fokker's Bond Tester, resonance characteristics (Δf) of the coupled system between. plastic materials and a transducer were experimentally and theoretically studied. As the materials, fiber reinforced plastics (FRP), plastics/metal lapped sheets and FRP with artificial defects were used. Δf of such materials were compared with those of sound polymethylmethacrilate sheets. Δf of FRP with artificial defects were also compared with those of FRP delaminated by fatigue tests. Possibility of detection of such delamination was examined experimentally.
A characteristic curve of Δf of polymethylmethacrilate sheets was found to resemble the modified curves of FRP, plastics/metal lapped sheets and etc.. The curves of Δf of FRP with artificial defects were nearly equal to that of FRP delaminated by fatigue tests. The size of the smallest defects in FRP which can be detected by the instrument was proportional to the bottom area of transducers. The size was influenced also by the thickness of the upper and the lower zones of specimens.
