Numerical and Experimental Investigation of Fatigue Crack Growth Behavior in Inhomogeneous Material Domains

This thesis investigates fatigue crack growth in engineering materials with inhomogeneous properties introduced by welding and additive manufacturing. It focuses on fatigue behavior of friction stir welded magnesium joints, dissimilar aluminium?steel joints, and stainless steel repaired using wire arc additive manufacturing. The inhomogeneous material domains significantly influence crack propagation under fatigue loading, making their behavior difficult to predict. Using experiments and numerical simulations, the study examines the influence of dissimilar materials and microstructure on fatigue behaviour. The findings enhance understanding of fatigue in varied material systems and provide reliable assessment of structural performance for aerospace, automotive, and marine applications.