Quantification of strain-induced damage in semi-crystalline polymers: a review

Semi-crystalline polymers are now extensively used in various applications such as aircrafts, civilian structures, oil and gas platforms and electronics. They are, however, inherently damage prone, and over time, the formation of damages such as cavitation and crazing causes degradation in mechanical properties, which eventually results in the permanent failure of the materials. This paper provides an overview of the principal approaches to assess and characterize damage in semi-crystalline polymers. The damage characterization methods are divided into two categories: mechanical characterization methods, aiming at describing damage growth based on the measurement of mechanical or physical properties and structural characterization methods, focusing on the assessment of microdamage initiation and evolution. Special attention has been paid to in situ non-destructive damage characterization methods. For better understanding deformation/damage behavior in semi-crystalline polymers, two major damage theories currently used to describe damage development are also described. The paper concludes with a discussion of limitations and critical issues for characterizing damage in semi-crystalline polymers.