Abstract: | A comparison of the temperature-time dependences of the strength of highly oriented fibers under static and cyclic loading shows that in the region of high temperatures and low loading frequencies the static and cyclic specimen lives always coincide. The discrepancy between the static and cyclic lives observed in the region of low temperatures and higher loading frequencies is related with differences in the structural changes in the different loading regimes. These changes are relaxational in nature.The experimental data were reported at the 14th and 16th All-Union Conferences on High-Molecular Compounds (1964 and 1966).A. F. Ioffe Physicotechnical Institute, Leningrad. Translated from Mekhanika Polimerov, Vol. 4, No. 4, pp. 648–655, July–August, 1968. |