This innovative work, titled "Strong yet ductile heat-resistant aluminum alloy by additive manufacturing," was published in the Nature journal Nature Communications, drawing significant attention from both academia and industry.
April 17, 2026 – A major breakthrough in the design and manufacturing of advanced aluminum alloys has been achieved by a team led by Professor Jian Lu of the Hong Kong Institute for Advanced Study, City University of Hong Kong, in collaboration with Professor Xinping Mao of the University of Science and Technology Beijing, Professor Qiang Zhu of Southern University of Science and Technology, and Jiangxi Baohang New Materials Co., Ltd.
The research team successfully produced a low-cost, low-density Al-7.44Si-2.34Fe-1.79Mn-1.12Ni alloy using laser powder bed fusion (PBF-LB) 3D printing technology. This achievement represents a significant advancement in high-temperature aluminum alloy additive manufacturing.
The alloy contains no precious metals or rare earth elements. Instead, it leverages the non-equilibrium segregation of common impurity elements (Si, Fe, Mn, Ni) in aluminum alloy under rapid solidification. By embedding heat-resistant multi-component intermetallic nanoprecipitates (HMINPs) at the solidification cell boundaries, the team achieved a thermally stable cellular microstructure with uniformly distributed HMINPs at the cell boundaries, reaching a volume fraction as high as 14%. Without any post-treatment, the alloy exhibits a tensile strength of 582 MPa at room temperature, 263 MPa at 300°C, and 114 MPa at 400°C. It also demonstrates excellent creep resistance at 400°C, indicating its potential for long-term service under extreme high-temperature conditions.
What is even more remarkable is that some of the HMINPs undergo a solid-state amorphization transformation during high-temperature deformation, ultimately forming a nanoscale dual-phase structure of "amorphous + nanoparticles" – specifically, an amorphous matrix uniformly decorated with ultra-small (sub-5 nm) ordered L1₂ γ'-(Ni,Fe)₃Al precipitates. This solid-state amorphization toughening mechanism, observed for the first time in bulk aluminum alloys, provides an additional energy dissipation pathway during high-temperature deformation. This helps prevent crack propagation and preserves excellent mechanical properties at elevated temperatures.
The corresponding authors are Professor Jian Lu (City University of Hong Kong) and Professor Qiang Zhu (Southern University of Science and Technology). The first authors are Dr. Gan Li (postdoctoral fellow at City University of Hong Kong) and Dr. Yuhe Huang (lecturer at University of Science and Technology Beijing).
