Carbon engineering in eutectic high-entropy alloys

Xiaoyu Bai; Dingcong Cui; Chuwen Wang; Yuhao Jia; Zhongsheng Yang; An Xie; Bokun Zhang; Jianbin Wang; Chuanyun Wang; Junjie Li; Feng He; Jincheng Wang; Xiaoguang Fan; Hyoung Seop Kim; Zhijun Wang

doi:10.59717/j.tiis.2026.100014

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Carbon engineering in eutectic high-entropy alloys

1.
-State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China
2.
Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
3.
Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai 980-8577, Japan

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Corresponding authors: fxg3200@nwpu.edu.cn (X.F.); hskim@postech.ac.kr (H.S.K.); zhjwang@nwpu.edu.cn (Z.W.)
Received Date: May 14, 2026

Accepted Date: September 30, 2026

Published Online: September 30, 2026

The Innovation Insights https://doi.org/10.59717/j.tiis.2026.100014 | Cite this article

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GRAPHICAL ABSTRACT

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PUBLIC SUMMARY

PUBLIC SUMMARY
1. Carbon is a key element for tailoring the nucleation kinetics of eutectic high-entropy alloys (EHEAs).
  
  Carbon-induced eutectic structures endow the EHEA with an exceptional combination of strength and ductility.
  
  The proposed "carbon engineering" strategy can stimulate intensive research across the EHEA field.

ABSTRACT

ABSTRACT

Over the past decade, eutectic high-entropy alloys (EHEAs) with FCC and B2 phases have shown outstanding performance as advanced structural materials. Extensive efforts within the metallurgy community have established the thermodynamics-guided paradigm for eutectic synthesis. Here, we open a new frontier in physical metallurgy by exploiting carbon as a kinetic activator of eutectic solidification in EHEAs. Even trace carbon additions profoundly modified the eutectic transition, transforming hypereutectic structures into fully coupled FCC/B2 eutectics. With increased concentrations, carbon further induced decoupled FCC/B2 growth followed by a secondary FCC/carbide eutectic transformation, resulting in separated FCC and B2 dendrites together with high-density nanoscale M₇C₃ carbides. Multi-scale analyses reveal that carbon interstitials and carbides play an intriguing role in accelerating the nucleation kinetics. Across a broad range of additions, the tailored microstructures imparted an exceptional strength-ductility synergy in EHEAs. We found that interstitial carbon significantly enhanced dislocation storage and promoted the coordination of multiple slip modes, while the FCC/M₇C₃ nano-eutectics formed under high carbon content constructed a unique mechanical transition layer for global co-deformation. These discoveries establish “carbon engineering” as a powerful, kinetics-based strategy for EHEA design, pioneering new directions in advanced eutectic materials research.
- carbon /
- eutectic high-entropy alloy /
- eutectic design /
- nucleation kinetics /
- strength-ductility synergy

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Bai X., Cui D., Wang C., et al. (2026). Carbon engineering in eutectic high-entropy alloys. The Innovation Insights 1:100014. https://doi.org/10.59717/j.tiis.2026.100014

Bai X., Cui D., Wang C., et al. (2026). Carbon engineering in eutectic high-entropy alloys. The Innovation Insights 1:100014. https://doi.org/10.59717/j.tiis.2026.100014

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Carbon engineering in eutectic high-entropy alloys

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