Characterization and failure ... Physical Testing of Thermoplastics. Mechanical properties of polymers ... Thermosetting polymers. Polymer testing. Tensile Creep and Deformation Modeling of Vinyl Ester Polymer and Its Nanocomposite. Viscoelastic Properties of an Epoxy Resin during Cure. Daniel J. O'Brien Patrick T. Mather Scott R. The cure dependent relaxation modulus of an epoxy resin was investigated over the entire range of cure extent. Selection of Polymeric Materials - How to Select Design Properties from Different Standards. Creep (deformation) The rate of deformation is a function of the material properties, exposure time, exposure temperature and the applied structural load. Depending on the magnitude of the applied stress and its duration, the deformation may become so large that a component can no longer perform its function — for example creep of a turbine blade will cause the blade to contact the casing, resulting in the failure of the blade.
Creep is usually of concern to engineers and metallurgists when evaluating components that operate under high stresses or high temperatures. Creep is a deformation mechanism that may or may not constitute a failure mode. For example, moderate creep in concrete is sometimes welcomed because it relieves tensile stresses that might otherwise lead to cracking. The temperature range in which creep deformation may occur differs in various materials. Strain as a function of time due to constant stress over an extended period for a viscoelastic material. where where: