Tensile fatigue strength in unidirectional CFRP depends on time and tempera
ture as well as number of cycles. A prediction method of fatigue strength p
roposed [14] for polymer composites meeting certain conditions and confirme
d for flexural fatigue strength of satin-woven CFRP laminates is applied to
the tensile fatigue life of unidirectional CFRP. The method is based upon
the four hypotheses: (A) same failure mechanisms for constant strain-rate (
CSR), creep, and fatigue failure, (B) same time-temperature superposition p
rinciple for all failure strengths, (C) linear cumulative damage law for mo
notonic loading, and (D) linear dependence of fatigue strength upon stress
ratio. Data are provided for tensile CSR, creep, and fatigue tests at vario
us temperatures in the longitudinal direction of unidirectional CFRP. Exper
imental verification of the prediction method for the tensile fatigue stren
gth of the unidirectional CFRP is presented.