Fracture testing of polymer materials processed via fused filament fabrication: a survey of materials, methods, and design applications

Additive manufacturing (AM) provides a wide range of design freedoms, enabling engineers to create complex geometries. However, due to the inherent nature of the manufacturing process, defects are introduced in the material during AM. These defects may develop into cracks and lead to failure of the system at lower loads than predicted from datasheets for traditionally manufactured materials. Thus, it is essential for design engineers to understand fracture properties of AM materials. The fracture mechanics can provide valuable inputs for design-related decision making (for both material design and macro-scale product design) to minimize possibility of failure. This article collected and reviewed the relevant literature on fracture testing of AM-fabricated polymer materials. Information on the testing methods used, the materials and processes, and the standards followed were collected and discussed in terms of their impact on design perspectives. In addition to collecting a dataset and establishing the state-of-the-art, this article identified opportunities and areas that need further studies, discussed design-centric interpretations of AM polymer fracture data, and provided recommendations on how to improve future studies and ensure the data is useful for consideration during engineering design.