Details

Autor(en) / Beteiligte

• Felice, Igor O.
• Shen, Jiajia
• Barragan, André F.C.
• Moura, Isaque A.B.
• Li, Binqiang
• Wang, Binbin
• Khodaverdi, Hesamodin
• Mohri, Maryam
• Schell, Norbert
• Ghafoori, Elyas
• Santos, Telmo G.
• Oliveira, J.P.

Titel

Wire and arc additive manufacturing of Fe-based shape memory alloys: Microstructure, mechanical and functional behavior

Ist Teil von

• Materials & design, 2023-07, Vol.231, p.112004, Article 112004

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• [Display omitted] •A novel iron-based shape memory alloy was successfully deposited by wire and arc additive manufacturing.•As-deposited material was predominantly composed by FCC γ phase with a columnar dendritic morphology.•High mechanical performance was observed for yield strength, fracture stress, elongation, cyclic repetibility and hardness.•Uniaxial loading induced the FCC γ → HCP ε phase transformation and resulted in a ductile fracture. Shape memory alloys (SMA) are a class of smart materials with inherent shape memory and superelastic characteristics. Unlike other SMAs, iron-based SMAs (Fe-SMA) offer cost-effectiveness, weldability, and robust mechanical strength for the construction industry. Thus, applying these promising materials to advanced manufacturing processes is of considerable industrial and academic relevance. This study aims to present a pioneer application of a Fe–Mn–Si–Cr–Ni–V-C SMA to arc-based directed energy deposition additive manufacturing, namely wire and arc additive manufacturing (WAAM), examining the microstructure evolution and mechanical/functional response. The WAAM-fabricated Fe-SMAs presented negligible porosity and high deposition efficiency. Microstructure characterization encompassing electron microscopy and high energy synchrotron X-ray diffraction revealed that the as-deposited material is primarily composed by γ FCC phase with modest amounts of VC, ε and σ phases. Tensile and cyclic testing highlighted the Fe-SMA's excellent mechanical and functional response. Tensile testing revealed a yield strength and fracture stress of 472 and 821 MPa, respectively, with a fracture strain of 26%. After uniaxial tensile loading to fracture, the γ → ε phase transformation was clearly evidenced with post-mortem synchrotron X-ray diffraction analysis. The cyclic stability during 100 load/unloading cycles was also evaluated, showcasing the potential applicability of the fabricated material for structural applications.