Zibin Chen, an assistant professor in industrial and systems engineering at The Hong Kong Polytechnic University, led researchers who announced on Oct. 24, 2026, two breakthroughs addressing cold brittleness in alloys. Phys.org reported that the group achieved materials combining strength, ductility and toughness at 77 K, about −196°C.
By applying a nanoscale interface method, the group restructured a metal internally, creating materials with strength, ductility and toughness at cryogenic temperatures. The research appeared in two successive studies in Nature Communications and offers a high-performance, scalable material base for future deep-sea and deep-space exploration gear. Phys.org described the combination as unmatched.
The multi-principal element alloy NiCoCr-AlTa — an alloy containing several principal elements rather than one dominant base metal — combines nickel, cobalt, chromium, aluminum and tantalum and sets a new benchmark for cryogenic alloys at liquid-nitrogen temperatures. At those temperatures it posts a yield strength of about 1.30 GPa, an ultimate tensile strength of about 1.80 GPa, tensile ductility of 50% and fracture toughness of about 213 MPa·m^1/2. Thick layered stacking faults help the alloy harden under strain and tolerate damage, producing what the researchers described as record-breaking cryogenic mechanical traits. PolyU observed and described the new microstructures using advanced electron microscopy and mechanical evaluation tools.
The group also produced a hierarchical nano-orderings NiCoCr-based alloy that posts a yield strength of about 2.0 GPa, an ultimate tensile strength of about 2.4 GPa and uniform tensile ductility of 22% when tested at liquid-nitrogen temperatures. The negative-curvature interface approach alters the surface shape of nanoscale particles inside the metal, letting it bear heavy loads while staying able to bend and lowering the chance of abrupt breaking.
According to Chen, the negative-curvature interface approach remakes nanoscale inner particles from basic strengtheners into adjustable agents that govern deformation while the metal bears weight. The concept arose from studying how nanoparticles change energetically as they coarsen. Chen said the work establishes a new area in advanced material design and offers a low-cost, scalable path to high-performance structural materials for industry.
Chen added that the method works for all precipitation-hardened alloy systems, including superalloys, age-hardening steels and aluminum alloys. Standard smelting, rolling and short-term aging can produce NiCoCr-AlTa instead of complex new processes, creating a foundation for large-scale production and engineering use. The researchers plan to test industrial-scale samples next, hoping to move the research toward commercial use in the coming decade.
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