This study was done to clarify the influence of complex deterioration on fatigue reliability. Carbon fiber reinforced and glass fiber reimforced PEEK (poly-ether-ether-keton) that is thermal plastic was examined to construct the life cycle design intended to decrease environmental stresses. Specially, the influence of recycling process and high environmental temperature on the fatigue reliability of fiber-reinforced PEEK were experimentally examined. Main results were as follows ; (1) It was noted that the S-N curves of recycled PEEK/CF and PEEK/gf materials were as nearly equal to that of virgin material. (2) The macro crack has been initiated on specimen at fatigue limit (N=107 cycle) of recycled gf material, and its crack was not propagated. On the other side, it has been not initiated on CF materials whether Virgin or recycled material. (3) The influence of the declining of fiber length by recycling process on fatigue strength of PEEK materials was small. (4) The influence of recycling process on PEEK/CF and PEEK/gf material could not be found by the fractograhy using SEM and the measuring of temperature rise on surface of specimen. So it was understood that the fracture mechanism of recycled material is squal to that of virgin material. (5) The results of fatigue crack propagation test to make clear the non-propagation crack showed that the fatigue propagation property of recycled material is equal to that of virgin material.
