Enhancing the Age‐Hardening Response of Laser Powder‐Bed Fusion WE43 Alloy through Microstructural Control

Age‐hardening is the main strengthening mechanism for obtaining high‐strength WE43 alloy components traditionally produced via casting. Laser powder‐bed fusion (L‐PBF) can produce high‐density WE43 parts. However, standard postprocessing heat treatment parameters (T6) used for conventional WE43 lead to inferior mechanical performance in L‐PBF WE43. Herein, the effect of direct aging (T5) and artificial age‐hardening treatment (T6) under varying temperature and duration on the resulting microstructure and mechanical properties of L‐PBF WE43 is investigated via in‐depth microstructural and mechanical characterization. The grain structure, orientation, texture as well as the size and morphology of β₁‐Mg₃Nd precipitates are analyzed via electron backscatter diffraction and transmission electron microscopy. Superior ductility is determined upon optimized T6 treatment (550 °C, 4 h/200 °C, 8 h) in comparison to the direct aging (200 °C, 8 h) of L‐PBF WE43 due to the dissolution of neodymium‐rich particles during solutionizing potentially allowing finer and more homogeneous particle distribution. The direct aging of L‐PBF WE43 shows an improvement in microhardness (93.5 Hv0.2) and tensile strength (260.1 MPa) with reduced ductility compared to as‐built L‐PBF WE43. A combination of high strength (UTS: 263.1 MPa)/hardness (85.2 Hv0.2) along with good ductility (6.1%) is achieved by optimizing T6 treatment for L‐PBF WE43.