Fracture mechanics test standards for fiber-reinforced polymer composites: Suggestions for adapting them to Industry 4.0 and the digital age

Abstract

Fracture mechanics is expected to play an increasingly important role in design and development of components or structural elements made of fiber-reinforced polymer-matrix (FRP) composites, e.g., from carbon fiber epoxy. Test standard development in this sector has been slow. However, there are additional issues that impede implementation of the existing standards in Industry 4.0 and the digital age test facilities. Selected examples focus on recent developments in digital technologies, specifically imaging and image analysis and use of nondestructive test methods as well as handling of big data. Using these tools will reduce scatter (e.g., in determination of delamination lengths) and dependence on operator experience or qualification (i.e., the "human factor"). Further aspects discussed are automated data analysis and data fitting for evaluating materials properties, or for providing data for modelling and simulation of fracture behavior. It is argued that test set-ups with non-destructive delamination monitoring combined with automated analysis will efficiently provide reliable data for fracture mechanics based FRP structural design. Such data can also be compiled in data bases, e.g., for suppliers’ data sheets or for comparing different FRP composites for use in structural applications. This is expected to have effects on the quality of data and on the test requirements as well as the related cost.