As an alternative to the conventional steel fabrication processes, additive manufacturing (AM) of steel is rapidly gaining popularity due to the free-form capabilitiesfor the optimal use of material and flexibility in adapting a fabrication procedure to the shape and expected volume of the additive material. Among the different AM processes, the most suitable for large-scale parts and serial production, in terms of speed and accuracy of use, is wire and arc additive manufacturing (WAAM).

The WAAM fabricated parts undergo fast cooling, which may result in internal defects and/or non-homogeneous material properties. This has an important influence primarily on the strength of the structural component, residual stresses and distortions. These challenges are even more important in the case of fatigue-sensitive applications.