Designing for cooperative grain boundary segregation in multicomponent alloys

• 成果类型: Article
• 署名作者: Wagih, Malik; Naunheim, Yannick; Lei, Tianjiao; Schuh, Christopher A.
• 署名单位: Massachusetts Institute of Technology (MIT); United States Department of Energy (DOE); Lawrence Livermore National Laboratory; Northwestern University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12418
• DOI: 10.1073/pnas.2511930122
• 发表日期: 2025-09-23
• 关键词: structural model; al; thermodynamics; BEHAVIOR

摘要

Tailoring the nanoscale distribution of chemical species at grain boundaries is a powerful method to dramatically influence the properties of polycrystalline materials. However, classical approaches to the problem have tacitly assumed that only competition is possible between solute species. In this paper, we show that solute elements can cooperate in the way they segregate to grain boundaries: In properly targeted alloys, the different chemical species cooperate to each fill complementary grain boundary sites disfavored by the other. By developing a theoretical spectral approach to this problem based on quantum-accurate grain boundary site distributions, we show how grain boundaries can be cooperatively alloyed, whether by depletion or enrichment. We provide machine-learned cosegregation information for over 700 ternary aluminum-based alloys and experimentally validate the concept in one ternary alloy where cosegregation is not expected by prior models but is expected based on the cooperative model.