Multimodal non-destructive evaluation approach for damage quantification

The prevailing materials-by-design concept for advanced applications in energy, automotive, aerospace, mechanical and civil industries greatly depends on the ability to identify and quantify critical relationships between reversible/irreversible (micro) structural changes and deformation/damage mechanisms. . Despite the advances in this field, the need for actual quantified and cross-validated NDE information across length scales is of paramount importance for i) understanding fundamental aspects in material development, e.g. plasticity and fracture, ii) linking developing damage with applied loading conditions from both environment and structural design, and iii) continuously monitoring the operation of critical infrastructures e.g. in commercial aircrafts. This paper presents a framework for damage quantification in fiber metal laminates such as GLARE used primarily for aerospace applications. This approach is based on the systematic mechanical testing of its constituents (metals, fibers and fiber-reinforced polymers) coupled with the synchronous use of two complimentary NDE methods such as Acoustic Emission (AE) and Digital Image Correlation (DIC) to reliably track the two important stages related to damage, i.e. damage initiation and subsequent (and progressive) damage development. Additionally, numerical simulations are performed to capture important aspects of the mechanical behavior of GLARE and in turn assist the interpretation of the obtained experimental results. In addition to the experimental and computation work, an information post-processing scheme that is based on smart filtering and damage sensitive feature extraction is presented to address the challenging task of damage identification in GLARE.