Additive Manufacturing Techniques for Metallic Alloys and Components

Additive manufacturing (AM) of metallic alloys encompasses a suite of layer-by-layer fabrication methods that build complex geometries directly from digital models. Powder-bed fusion and directed energy deposition predominate for high-performance alloys, harnessing lasers or electron beams to locally melt or sinter metal powders or wires. These approaches enable unprecedented design freedom, weight reduction, and part consolidation, while presenting challenges in microstructural control, residual stress management and defect mitigation. Recent advances focus on tailoring melt-pool dynamics and solidification pathways to refine grain structure, promote isotropic properties and reduce anisotropy. Complementary methods—such as material extrusion of highly filled polymers or binder-jetting followed by sintering—extend AM to bulk components, balancing resolution with throughput. Altogether, metallic AM is transforming aerospace, biomedical and energy industries through both bespoke component fabrication and rapid design iteration.

Research from Nature Portfolio

Recent studies demonstrate that feedstock powder size can be leveraged to engineer grain morphology in stainless steel components without altering hardware. Fine powders promote coarse, near-monocrystalline structures, whereas coarse powders yield fine, equiaxed grains through particle-size-dependent thermal preheating and powder-bed thermophysics. This simple adjustment applies to both directed energy deposition and powder-bed fusion, enabling cost-effective microstructure control. Complementary work has elucidated the crucial role of side-branching in laser powder-bed fusion: dendritic perturbations on melt-pool peripheries enable grains to reorient in response to local heat-flux variations, disrupting epitaxial columnar growth and enhancing grain broadening. Scan-strategy manipulations further intensify orthogonal and helical branching modes, offering a pathway to tailor texture and mechanical performance through thermal-gradient engineering.

Additive Manufacturing Techniques for Metallic Alloys and Components publication trend

The graph below shows the total number of articles in additive manufacturing techniques for metallic alloys and components across all publications each year (not limited to Nature Index journals).

Technical terms

Laser Powder-Bed Fusion: An AM process that uses a focused laser to selectively melt successive layers of metal powder according to digital cross-sections.

Directed Energy Deposition: A technique in which metal powder or wire is delivered into a melt pool created by a laser or electron beam to build parts layer by layer.

Melt Pool: The localized volume of molten material formed and resolidified during each energy-input pass in powder- or wire-based AM processes.

Columnar-to-Equiaxed Transition: The shift from elongated, directionally grown grains to roughly equiaxed grains during solidification, affecting mechanical isotropy.

Side-Branching: The formation of secondary dendritic arms perpendicular to primary crystal growth that modifies grain morphology in response to thermal gradients.

References

1. Additive Manufacturing of Metallic and Ceramic Components by the Material Extrusion of Highly-Filled Polymers: A Review and Future Perspectives. Materials (2018).
2. Powder-size driven facile microstructure control in powder-fusion metal additive manufacturing processes. Nature Communications (2024).
3. The role of side-branching in microstructure development in laser powder-bed fusion. Nature Communications (2020).
4. Recent advances in inoculation treatment for powder-based additive manufacturing of aluminium alloys. Materials Science and Engineering R Reports (2024).
5. Investigation of the grain deformation to orthogonal cutting process of the textured Alloy 718 fabricated by laser powder bed fusion. International Journal of Machine Tools and Manufacture (2023).
6. Additive manufacturing of steels: a review of achievements and challenges. Journal of Materials Science (2020).