Deformation Under Load
Measure of the ability of rigid plastics to withstand permanent deformation and the ability of nonrigid plastics to return to original shape after deformation.
- Rigid plastics - deformation (flow or flow and shrinkage) is re-ported as % change in height of specimen after 24 hours under a specified load.
- Nonrigid plastics - results are reported as % change in height after 3 hours under load and recovery in the 1-1/2 hour period following removal of the load. Recovery is % increase in height calculated on basis of original height.
ASTM D621 - Test Methods for Deformation of Plastics Under Load
ASTM D2990 - Standard Test Methods for Tensile, Compressive, and Flexural Creep and Creep-Rupture of Plastics
See also: Deformation.