Ultrahigh strength-ductility synergy via heterogeneous grain structure and multi-scale L1 2-γ ′ precipitates in a cobalt-based superalloy GH159

被引：3

作者：

Chen, Guidong ^{[1
]}

Liu, Fei ^{[1
]}

Chen, Fei ^{[1
]}

Tan, Yuanbiao ^{[1
]}

Cai, Yeqing ^{[1
]}

Shi, Wei ^{[1
]}

Ji, Xuanming ^{[1
]}

Xiang, Song ^{[1
]}

机构：

[1] Guizhou Univ, Coll Mat & Met, Key Lab Mech Behav & Microstruct Mat Guizhou Prov, Natl & Local Joint Engn Lab High Performance Met S, Guiyang 550025, Peoples R China

来源：

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING | 2024年 / 904卷

基金：

中国国家自然科学基金;

关键词：

Cobalt-based superalloys; Strength-ductility synergy; Dual heterogeneous structures; Heat treatment; L1 2-gamma ' precipitation; HIGH-ENTROPY ALLOYS; NANO-TWIN; DEFORMATION; DISLOCATION; BEHAVIOR; CRCONI;

D O I：

10.1016/j.msea.2024.146687

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Achieving excellent strength-ductility synergy through convenient techniques is highly desirable for modern engineering applications. In this study, we constructed a heterogeneous grain structure consisting of large residual deformed grains and fine recrystallized grains, along with multi-scale L1 2 - gamma ' precipitates, in a commercial cobalt-based superalloy GH159. This was achieved via short -term annealing followed by subsequent aging. The mechanical properties were significantly enhanced, demonstrating an exceptional ultimate tensile strength of 1611 MPa, and outstanding uniform and total elongations of 23.5 % and 34.7 %, respectively. We investigated the evolution of the dual heterogeneous structures and the corresponding strengthening mechanisms during deformation. Hetero-deformation induced (HDI) strengthening, L1 2 - gamma ' precipitation strengthening, along with nanotwins, L -C locks, and 9R phases contribute significantly to the excellent strength-ductility synergy in GH159. These findings offer a strategy for developing GH159 as a structural material for various engineering applications, providing accessible and cost-effective processing methods that pave the way for large-scale industrial production. Furthermore, this study provides design insights for enhancing the mechanical properties of cobaltbased precipitation-strengthened superalloys.

引用

页数：14