Prediction methodology for fatigue crack growth behaviour in Fibre Metal Laminates subjected to tension and pin loading Wandong Wang a,* , Calvin Rans a , Zhinan Zhang b , Rinze Benedictus a a Structural Integrity & Composites Group, Faculty of Aerospace Engineering, Delft University of Technology, P.O. Box 5058, 2600 GB Delft, The Netherlands 5 b The First Aircraft Design and Research Institute of AVIC, Xi , an 710089,China Abstract Fibre Metal Laminates (FMLs) are a hybrid metal-composite laminate technology known for their superior resistance to fatigue crack growth compared to monolithic metals. This crack growth behaviour has been the subject of many studies, resulting in numerous empirical and analytical models to describe the complex damage growth phenomenon in the material. This study builds upon the analytical Alderliesten crack growth prediction methodology for FMLs, extending it from a tension loaded plate to a case of a combined tension-pin loaded plate. This new loading case is a more representative case to utilise for predicting fatigue crack growth behaviour in mechanically fastened joints. Development of the model extension and validation through experimental testing are detailed within this paper. Keywords: pin loading, fibre metal laminates, crack growth behaviour 1. Introduction Fibre Metal Laminates (FMLs) are a material technology known for their superior fatigue 10 crack growth behaviour. This favourable behaviour is a result of the fibre bridging mech- anism whereby the intact fibre layers provide an alternative load path around the cracked metal layers, reducing stress in front of the crack tip (see Fig.1). Although the basic concept of fibre bridging is simple to understand, it proved to be a complex phenomenon to capture effectively in crack growth prediction models for FMLs. 15 Early attempts at predicting fatigue crack growth took a phenomenological approach, treat- ing an FML as a bulk material and developing empirical β correction factors to represent the contribution of the fibre bridging mechanism. These β corrections were then used to correct the standard stress intensity factor solutions used in the Linear Elastic Fracture Mechanics approaches for crack growth prediction in monolithic materials [1–3]. Additional 20 phenomenological approaches based on treating FMLs as a bulk material include the com- pliance method of Takamatsu [4], bridging stress linearization approach of Cox [5], and the * Corresponding author. Tel.: +31 (0)65 793 6757; E-mail address: w.wang-3@tudelft.nl Preprint submitted to Composite Structures September 22, 2017