2. Precautions for use

The properties are measured on test specimens whose processing is standardized and, in reality, the values can be significantly different for many reasons, for example :

• presence of additives of any kind: nucleophilic colorants, functional plasticizers, carbon fibers or black, release agents, antistatic agents, regrind;

• processing conditions leading to variations in crystallinity, orientation of macromolecules and reinforcements, physical defects such as weld lines... ;

• finishing: surface treatment, painting, assembly...

Part geometry can create notch effects or stress concentrations.

Test temperatures are 20 C or 23 C, which is not necessarily the operating temperature. For some materials, a small difference in...