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This work deals with the investigation and characterization of Ti6Al4V parts produced with an intriguing manufacturing process belonging to the Wire Arc Additive Manufacturing (WAAM) family: the Cold Metal Transfer technology (CMT). Wall‐shaped parts were produced according to different process parameters, namely the wire feed speed and voltage–current combinations, leading to different energy inputs. The parts were characterized in terms of surface morphology, microhardness, microstructure, tensile properties, and fatigue crack growth. The results suggested that the investigated deposition parameters led to similar results. Moreover, the mechanical and fatigue crack growth behavior was in line with parts of the same alloy produced through other manufacturing routes, whereas the microstructure type was the result of the fast cooling of the molten material. Finally, considering the simple system adopted to avoid oxidation during the deposition stage, the results suggested that CMT is a promising manufacturing technique for titanium alloy semifinished parts. Highlights: Wall‐like parts made of Ti6Al4V alloy were produced through WAAM‐CMT technologySound parts with minimum oxidation were produced through a simple enveloping systemThe parts had properties similar to those of more traditional manufacturing routesThe microstructure, tensile, and fatigue crack growth behavior were quite isotropic [ABSTRACT FROM AUTHOR]

Three‐dimensional numerical analyses, using the finite element method (FEM), have been adopted to simulate fatigue crack propagation in a hollow cylindrical specimen, under pure axial or combined axial‐torsion loading conditions. Specimens, made of Al alloys B95AT and D16T, have been experimentally tested under pure axial load and combined in‐phase constant amplitude axial and torsional loadings. The stress intensity factors (SIFs) have been calculated, according to the J‐integral approach, along the front of a part through crack, initiated in correspondence of the outer surface of a hollow cylindrical specimen. The crack path is evaluated by using the maximum energy release rate (MERR) criterion, whereas the Paris law is used to calculate crack growth rates. A numerical and experimental comparison of the results is presented, showing a good agreement in terms of crack growth rates and paths. [ABSTRACT FROM AUTHOR]