The microstructure and mechanical properties of duplex stainless steel components fabricated via flux-cored wire arc-additive manufacturing

Wire Laser Metal Deposition Additive Manufacturing of Duplex Stainless Steel Components—Development of a Systematic Methodology

“…In tensile testing, the similar behaviors of specimens oriented parallel to and perpendicular to the deposition direction demonstrate the isotropy of the tensile properties in this additively manufactured component. This was in contrast with the results of Zhang et al [ 23 ] who reported up to 11% anisotropy of tensile properties in WAAM with a 2209 DSS wire.…”

“…It has been demonstrated in this and other studies that additive manufacturing can be used to build DSS components, although achieving a desired microstructure and properties can be a challenge, as discussed in the introduction [ 13 , 14 , 15 , 16 , 17 , 18 , 23 , 24 , 25 , 26 ]. Figure 12 summarizes some important factors during production, the tools available to predict the resulting microstructure, and important properties that need to be controlled.…”

“…In all cases, an excessive amount of ferrite was a problem in the microstructures of the additively manufactured parts, and a post-heat treatment was necessary to balance ferrite and austenite fractions. Wire-arc additive manufacturing (WAAM) of DSS has also attracted widespread interest due to the affordable equipment and its high deposition rate [ 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ]. Zhang et al [ 22 ] observed an unbalanced microstructure with a high fraction of austenite in WAAM of super DSS.…”

“…Zhang et al [ 22 ] observed an unbalanced microstructure with a high fraction of austenite in WAAM of super DSS. In another study, it was reported the WAAM of 2209 DSS wire led to the formation of more than 70% austenite [ 23 ]. In addition to the formation of a high austenite fraction, WAAM lacks feature resolution and bead morphology control; consequently, the manufactured parts need significant machining [ 27 ].…”

Steel-copper functionally graded material produced by twin-wire and arc additive manufacturing (T-WAAM)

“…In region G, the hardness drops to around 180 HV, this result is associated with the change of HSLA steel constituents from polygonal a-ferrite + MA islands to a majority of coarse dendritic dferrite. The slight hardness increase to 200 HV in regions F and E was attributed to the dual-phase microstructure (d-Ferrite + Cu (FCC) constituents) and its multiple iterations, similar to what occurs in duplex stainless steels [20][21][22]. Towards the end of the interface, a smooth transition of hardness exists due to the continuous decrease in Fe (BCC constituents).…”