抄録
It was investigated how polyester fibers in a rubber matrix were fatigued and fractured by the model estimation method (disc and tube fatigue test). The results were discussed from the standpoints of fracture modes and morphologies. The fatigue rupture section under the disc fatigue, buckling phenomena, probably caused by the compressive shear stress. The breaking morphologies become more complicate with the increase of the compression ratio. In the case of the high adhesion strength between fiber and matrix rubber, a snap-back, round shape fiber ends were observed. On the other hand, for the poor adhesion, an acute knife-edge shape was observed. In the case of the tube fatigue, a “mushroom” shape probably by melt-rupture is presented. This suggests that the temperature of the fibers themselves becomes considerably high at the point of rupture. These morphologies are obviously different from those generated by simple tensile breaking and are characteristic for the fatigue.
