chapter  14
Durability
Pages 48

Aging can be defined as a slow and irreversible (in use conditions) variation of a material’s structure, morphology and/or composition, leading to a deleterious change of use properties. The cause of this change can be the proper material’s instability in use conditions or its interaction with the environment (oxidation, hydrolysis, photochemical, radiochemical, or biochemical reactions, etc.).