A high-temperature nanostructured Cu-Ta-Li alloy with complexion-stabilized precipitates

• 成果类型: Article
• 署名作者: Hornbuckle, B. C.; Smeltzer, J. A.; Sharma, S.; Nagar, S.; Marvel, C. J.; Cantwell, P. R.; Harmer, M. P.; Solanki, K.; Darling, K. A.
• 署名单位: United States Department of Defense; US Army Research, Development & Engineering Command (RDECOM); US Army Research Laboratory (ARL); United States Army; Lehigh University; Arizona State University; Arizona State University-Tempe; Louisiana State University System; Louisiana State University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-11960
• DOI: 10.1126/science.adr0299
• 发表日期: 2025-03-28
• 页码: 1413-1417
• 关键词: creep resistance; strength; BEHAVIOR; phase

摘要

We present a bulk nanocrystalline copper alloy that can operate at near-melting temperatures with minimal coarsening and creep deformation. The thermal stability of the Cu-3Ta-0.5Li atomic % (at %) alloy is attributed to coherent, ordered L12 Cu3Li precipitates surrounded by a tantalum-rich atomic bilayer phase boundary complexion. Adding 0.5 at % lithium to the immiscible Cu-Ta system changes the morphology of the nanoscale precipitates from spherical to cuboidal while simultaneously tailoring the phase boundary. The resultant complexion-stabilized nanoscale precipitates provide excellent thermal stability, strength, and creep resistance. The underlying alloy design principles may guide the development of next-generation copper alloys for high-temperature applications such as heat exchangers.