Significantly enhanced high-temperature mechanical properties of Cu-Cr-Zn-Zr-Si alloy with stable second phases and grain boundaries

Chengzhi Huang; Yanbin Jiang; Zixiao Wu; Meng Wang; Zhou Li; Zhu Xiao; Yanlin Jia; Huiwen Guo; Liye Niu

Materials & Design (Sep 2023)

Significantly enhanced high-temperature mechanical properties of Cu-Cr-Zn-Zr-Si alloy with stable second phases and grain boundaries

Chengzhi Huang,
Yanbin Jiang,
Zixiao Wu,
Meng Wang,
Zhou Li,
Zhu Xiao,
Yanlin Jia,
Huiwen Guo,
Liye Niu

Affiliations

Chengzhi Huang: State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China
Yanbin Jiang: State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China; School of Materials Science and Engineering, Central South University, Changsha 410083, China; Corresponding authors at: State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China (Y. Jiang).
Zixiao Wu: School of Materials Science and Engineering, Central South University, Changsha 410083, China
Meng Wang: School of Materials Science and Engineering, Central South University, Changsha 410083, China; Corresponding authors at: State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China (Y. Jiang).
Zhou Li: State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China; School of Materials Science and Engineering, Central South University, Changsha 410083, China
Zhu Xiao: School of Materials Science and Engineering, Central South University, Changsha 410083, China
Yanlin Jia: School of Materials Science and Engineering, Central South University, Changsha 410083, China
Huiwen Guo: Chinalco Luoyang Copper Processing Co. Ltd, 50 Jian She Road Luoyang, 471003, China
Liye Niu: Chinalco Luoyang Copper Processing Co. Ltd, 50 Jian She Road Luoyang, 471003, China

Journal volume & issue: Vol. 233
p. 112292

Abstract

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Improving high-temperature strength and resistance to high-temperature softening is an important method to promote the application of high-performance Cu-Cr-Zr alloy in fields such as resistance welding electrodes and high-speed railway contact wires. A Cu-1.0Cr-0.4Zn-0.1Zr-0.05Si alloy was designed and the combining effects of Zn and Si elements on the microstructure and high-temperature mechanical properties of the alloy were studied. The tensile strength of the alloy at room temperature was 556 MPa, and it was 349 MPa at 500℃ with a softening temperature of 620℃. The main strengthening phases of the alloy were submicron Cr3Si and nano-scaled Cr-rich precipitates. The Zn elements were uniformly solid-solved in the Cu matrix, and the addition of Zn and Si elements significantly retarded the phase transformation of the Cr-rich precipitates. Thermodynamics and kinetics analysis showed that Zn and Si elements promoted the dispersive precipitation of the nano-scaled FCC coherent Cr-rich precipitates by reducing the nucleation energy barrier, while the Si and Zr elements inhibited the coarsening of the Cr-rich precipitates by enriching at the phase boundaries, effectively impeding dislocation motion and grain boundary migration, which mainly contributed to good high-temperature strength and resistance to softening of the Cu-Cr-Zn-Zr-Si alloy.

Published in Materials & Design

ISSN: 0264-1275 (Print); 1873-4197 (Online)
Publisher: Elsevier
Country of publisher: United Kingdom
LCC subjects: Technology: Electrical engineering. Electronics. Nuclear engineering: Materials of engineering and construction. Mechanics of materials
Website: https://www.journals.elsevier.com/materials-and-design

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