Yangtze River Delta G60 laser alliance guide
澳洲墨尔本皇家理工大学、悉尼大学、香港理工大学及海克斯康制造智能（Hexagon Manufacturing Intelligence）公司的研究人员报道用3D打印造出高性能钛-氧-铁合金，助力解决“氧脆化”难题，将给物理冶金学带来广泛影响。 相关论文以“Strong and ductile titanium–oxygen–iron alloys by additive manufacturing”为题发表在《Nature》上。
Titanium alloys are advanced lightweight materials that are indispensable in many critical applications. The backbone of the titanium industry is α-β titanium alloys, which stabilize the α and β phases by adding alloys. The researchers' work focused on harnessing two of the most powerful stabilizing and strengthening elements in α-β titanium alloys, oxygen and iron, which are abundant in abundance. However, the brittleness of oxygen (commonly known as "titanium's kryptonite") and the micro-segregation of iron have hindered their bonding in the development of high-strength, high-plasticity α-β titanium-oxy-iron (Ti-O-Fe) alloys. Here, the researchers combined alloy design with additive manufacturing (AM) process design to present a range of alloys with excellent tensile properties of titanium-oxy-iron composition. The researchers used a variety of characterization techniques to explain the atomic-scale sources of these properties. The abundance of oxygen and iron, as well as the simple process of net-shaped or near-net-shape manufacturing by AM, make these α-β titanium-oxy-ferronickel alloys attractive in a variety of applications. In addition, the results of this research bring hope for the transformation of low-quality titanium sponge or sponge titanium oxide into high-performance titanium alloys and innovative alloy engineering.
图 1:DED打印Ti-O-Fe合金的微观结构。
Laser Directed Energy Deposition (L-DED) is an additive manufacturing (AM) process that enables the 3D printing of metal materials by laser melting metal powder particles and depositing them onto the surface. The researchers combined alloy design, computational simulation, and experimental characterization to plot the relationship between AM processes and microstructure and properties of an unprecedented α-β Ti-O-Fe alloy. The L-DED process was simulated by calculation, and the thermodynamic and electronic structures of the alloy were studied using computational thermodynamic methods and quantum mechanical methods, respectively. Rectangular alloy sheets were then fabricated using L-DED and subjected to tensile mechanical tests, while they were imaged using an advanced electron microscope and an atom probe microscope.
Figure 2: Tensile properties of a DED-printed Ti-O-Fe alloy at room temperature (with a focus on changing the alloy composition without changing processing conditions).
The Ti-O-Fe alloy in this study contains stable α and β phases and can be 3D printed using a variety of L-DED parameters. The microstructure of the alloy is ideal, with about 70% of the volume being oxygen-rich α and about 30% of the volume consisting of fine iron-rich β phase grains. α-β Ti-O-Fe alloys with an oxygen content of 0.3-0.5% are stronger than Ti-6Al-4V alloys with similar ductility and therefore have a variety of application potential at room temperature.
图 3：DED打印α-β Ti-O-Fe合金中O原子和Fe原子分布。
0.35O-3Fe-3Fe (:Ti-0.33O-3.11Fe)
Figure 5: APT 3D reconstruction data.
In summary, the researchers demonstrated the integration of alloy design and simulation-based AM process design to create a new class of high-strength, ductile α-β Ti-(0.35-0.50)O-3Fe alloys (εf = 9.0 ± 0.5% to 21.9 ± 2.2%; σUTS = 1,034 ± 9 to 1,194 ± 8 MPa). The researchers attribute the success of these alloys to the combination of multiscale microstructural features resulting from this integration.
Prof. Kenneth Chan (right), Chair Professor (Manufacturing Engineering) and Dr Chan Tsz-bun, Assistant Professor of the Department of Industrial and Systems Engineering of PolyU (left), have discovered that 3D printing technology can produce high-performance metal parts with the collaboration of traditionally unpopular oxygen. An innovative scheme that breaks through the limitations of traditional craftsmanship is proposed. Source: The official website of The Hong Kong Polytechnic University
In addition, zirconium sponge (Zr) is produced in the same way as titanium sponge. Therefore, it is expected that low-quality zirconium sponge can also be used to develop high-strength and toughness Zr-O-Fe alloys. In addition, this work provides potential avenues for gap engineering in AM in the future, such as mitigating nitrogen (N) brittleness in Ti and Zr and oxygen embrittlement in other metals.
Paper Links:
Song, T., Chen, Z., Cui, X. et al. Strong and ductile titanium–oxygen–iron alloys by additive manufacturing. Nature 618, 63–68 (2023). https://doi.org/10.1038/s41586-023-05952-6
Related Links:
https://www.nature.com/articles/d41586-023-01360-y
https://www.polyu.edu.hk/sc/media/media-releases/2023/0724_polyu-researchers-collaboratively-develop-high-performance-titanium-alloys/
Zhang, J., Liu, Y., Sha, G. et al. Designing against phase and property heterogeneities in additively manufactured titanium alloys. Nat Commun 13, 4660 (2022). https://doi.org/10.1038/s41467-022-32446-2
Nartu, M.S.K.K.Y., Welk, B.A., Mantri, S.A. et al. Underlying factors determining grain morphologies in high-strength titanium alloys processed by additive manufacturing. Nat Commun 14, 3288 (2023). https://doi.org/10.1038/s41467-023-38885-9
Reprinted by Chen Changjun of the Yangtze River Delta G60 Laser Alliance