A Novel γ′-Strengthened Nickel-Based Superalloy for Laser Powder Bed Fusion

Abstract

An experimental printable γ′-strengthened nickel-based superalloy, MAD542, is proposed. By process optimization, a crack-free component with less than 0.06% defect was achieved by laser powder bed fusion (LPBF). After post-processing by solution heat treatment, a recrystallized structure was revealed, which was also associated with the formation of annealing twins. After the aging treatment, 60–65% γ′ precipitates were obtained with a cuboidal morphology. The success of printing and post-processing the new MAD542 superalloy may give new insights into alloy design approaches for additive manufacturing.

Alloy Design and Characterization of γ′ Strengthened Nickel-based Superalloys for Additive Manufacturing

“…Here, '542' stands for the critical elemental concentration of 5 (wt.%) Mo, 4 (wt.%) W, and 2 (wt.%) Nb, which significantly improve (Mo, and Nb) or reduce (W) the additive manufacturability. In this chapter, the LPBF process and microstructures of MAD542 are presented and discussed [216]. The pre-alloyed gas atomized powders of the MAD542 superalloy were supplied by Höganäs AB, Sweden.…”

Effects of the Solution and First Aging Treatment Applied to As-Built and Post-HIP CM247 Produced Via Laser Powder Bed Fusion (Lpbf)

“…This was demonstrated in many literature works for SLM materials different from CM 247LC for example in the work of Calandri [37] for IN718. Xu came to similar conclusions on a 60 vol% γ' reinforced alloy called MAD542; in his work clearly explains the importance of the solution treatment to achieve the highest γ' volume fraction [38]. Also for HIPPed Astroloy, the solution temperature dramatically changed the γ' morphology and volume fraction [25].…”

Additive manufacturability of superalloys: Process-induced porosity, cooling rate and metal vapour

“…ExpAM-mod [41] and MAD542 [42] sit in the good additive manufacturability zone based on processinduced porosity (Figure 6), cooling rate (Figure 7) and mass loss results (Figure 8). This emphasises that new alloys are needed for the successful additive manufacturability [17,40] rationalised by thermal-fluid flow processing maps linked between compostion and process characteristics.…”