Crisp/Clean Break: Sear release without perceptible
creep.
Resistance to
creep is viewed [1-4] as a significant property of polymeric materials whenever end products are exposed to a more or less constant external force (dead load).
Creep corrosion is a process in which solid corrosion products (typically sulfide and chloride) migrate over a surface without the influence of an electric field.
The time parameters [t.sub.m]and [t.sub.0]are measures of the molecular mobility and, the smaller are these values, the more rapid is the
creep deformation.
The role of
creep to reduce induced tensile stress in restrained shrinkage has been recognised and included in methods to predict shrinkage cracking.
While Dyneema has some
creep, it also has some stretch, and there is a difference.
Contact them today for more information at imr@imrportland.com or visit their
Creep and Stress Rupture page at http://www.imrtest.com/What_we_do/Mechanical_Testing/CreepStress/index.html
Long-term
creep behavior might be predicted from short-term test data if the time-temperature-superposition principle is applicable to the studied material.
To understand the interplay of both kinetics and mechanics during post-curing, DMA
creep experiments were performed at various post-cure temperatures.
The molecular origins of
creep and physical aging are not fully understood, although it has been suggested that for semicrystalline polymers, such as polypropylene at room temperature, changes in the mechanical properties are attributable to changes in the conformation of the tie molecules coupled with the motion of chains through the crystal lamellae (3, 4).