The reliability of the damage tolerance approach to engineering design is affected by numerous sources of uncertainty that can lead to unsafe predictions, in turn jeopardizing the safety of structures. This work presents a robust stochastic framework for fatigue crack-growth predictions applied to a round bar under tension–compression loading conditions. Multi-source uncertainties were taken into account to derive the lifespan distribution for the bar in such a way to cover the uncertainties typically appearing in a structural integrity assessment. The sensitivity of each input variable was obtained and the influences of variables on the life predictions were derived and ranked accordingly.

The advent of additive manufacturing (AM) processes applied to the fabrication of structural components has created the need for design methodologies and structural optimization approaches that take into account the specific characteristics of the fabrication process. While AM processes give unprecedented geometrical design freedom, which can result in significant reductions in the components’ weight (e.g., through part count reduction), on the other hand, they have implications for the fatigue and fracture strength, because of residual stresses and microstructural features. This is due to stress concentration effects, anisotropy, distortions and defects whose effects still need investigation. This Special Issue aims at gathering together research investigating the different features of AM processes with relevance for their structural behavior, particularly, but not exclusively, from the viewpoints of fatigue, fracture and crash behavior. Although the focus of this Special Issue is on AM, articles dealing with other manufacturing processes with related analogies can also be included, in order to establish differences and possible similarities.