An investigation on the impact of the interpass-cooling time on the metallurgy of wire-arc-additive-manufacturing ss308l components

In this paper, we focused on observing the influence of the interpass-cooling time on the microstructure of stainless steel (SS308L) walls fabricated by the wire and arc additive manufacturing (WAAM) process. For this purpose, two SS308L walls were produced by WAAM according to the unidirectional depositing strategy with an interpass-cooling time of 30 (s) and 60 (s) between two consecutively deposited layers. The findings indicate that in terms of microstructures there is no significant difference between two as-built thin walls. The microstructure of WAAM SS308L walls contains dominant austenite phases and a small amount of ferrite, which exists in the boundaries of austenite grains. However, when the interlayer idle time increases the secondary dendrite arm spacing (SDAS) becomes narrow, resulting in an augmentation in the microhardness and tensile properties of as-built components. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2021.