ABSTRACT
This chapter introduces the concept of damage tolerance, sources of damage, and damage tolerance drivers. Among the sources of damage, impact-induced damage for many composite applications is considered as the primary damage concern. All of the factors raise questions as to how to achieve appropriate quantifiers for classifying the impact event, which can be useful in developing analytical measures for damage, damage growth, and subsequent failure. The damage zone is assumed to be identified by a characteristic dimension co, which can be considered as an effective flaw length. An analogy can be developed for the case of hard particle impact on a composite target to that of damage imparted by implanting a crack of fixed dimensions in a tensile coupon. The residual strength of the damaged specimen was determined in a tensile mode based upon an evaluation of the damage state using ultrasonic scanning.
