Mechanical testing of plastics - Rheological and thermal testing

This third article in the Mechanical Testing of Plastics series looks at :

• mechanical spectroscopy tests, to determine the rheological properties of solid-state polymers under transient or harmonic loads. It should be noted that the viscoelastic physical characteristics (moduli, damping capacities) measured in this way are in the linear (elastic) domain, and not at fracture;

• thermomechanical volume tests, the aim of which is to determine physical characteristics (coefficients of expansion) or technological characteristics (conventional temperatures), which estimate the influence of temperature on mechanical behavior;

• mechanical surface tests, which characterize the surface condition of parts either in the low-strain range (hardness), or at fracture (wear and surface brittleness), or in terms of roughness.