Methods for the prediction of fatigue delamination growth in composites and adhesive bonds – A critical review

• A historical overview of delamination growth methods is critically discussed.
• Four classes are defined: stress/strain based, LEFM based, CZM based, XFEM based.
• It is shown most models are in essence phenomenological.
• It is argued a stronger connection with the physical mechanisms is needed.

An overview is given of the development of methods for the prediction of fatigue driven delamination growth over the past 40 years. Four categories of methods are identified: stress/strain-based models, fracture mechanics based models, cohesive-zone models, and models using the extended finite element method. It is highlighted that most models are phenomenological, based on the observed macro-scale behaviour of test specimens. It is suggested that a more physics based approach, focusing on elucidating the mechanisms involved, is needed to come to a full understanding of the problem of delamination growth.