[Zurück]

R. Lach, W. Grellmann:
"Time- and Temperature-Dependent Fracture Mechanics of Polymers: General Aspects at Monotonic Quasi-Static and Impact Loading Conditions";
Macromolecular Materials and Engineering, 293 (2008), 7; S. 555 - 567.

Well-defined correlations exist between the maxima in mechanical loss factor and the local maxima in temperature- or loading-speed-dependent fracture toughness. The non-linear viscoelastic fracture processes and small-strain deformations are characterised by the same Arrhenius-type activation enthalpies. The local increase in toughness is linearly correlated with the relaxation strength of molecular relaxation processes. Stable crack propagation can be understood as a three-phase process resulting in steady-state stable crack growth. The normalised
steady-state crack-tip-opening displacement is independent of matrix material, temperature and loading speed.

Well-defined correlations exist between the maxima in mechanical loss factor and the local maxima in temperature- or loading-speed-dependent fracture toughness. The non-linear viscoelastic fracture processes and small-strain deformations are characterised by the same Arrhenius-type activation enthalpies. The local increase in toughness is linearly correlated with the relaxation strength of molecular relaxation processes. Stable crack propagation can be understood as a three-phase process resulting in steady-state stable crack growth. The normalised
steady-state crack-tip-opening displacement is independent of matrix material, temperature and loading speed.

activation energy, fracture mechanics, impact resistance, relaxation, toughness

http://dx.doi.org/10.1002/200700417