A novel NbC/CrMnFeCoNi0.8 high entropy alloy matrix composites with ultrastrength and ductility: Experiments and density function theory

• Published in: Composites communications Vol. 38; p. 101510
• Main Authors: Huang, Sirui, Wu, Hao, Chen, Yujie, Zhao, Zhenguo, Liu, Xiaoyan, Deng, Yuanbo, Zhu, Heguo
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2023
• Subjects: Composites; Density functional theory (DFT); Microstructure; Strengthening mechanism; Composites; Microstructure; Density functional theory (DFT); Strengthening mechanism
• ISSN: 2452-2139; 2452-2139
• DOI: 10.1016/j.coco.2023.101510

In this work, NbC particle-reinforced CrMnFeCoNi0.8 high-entropy alloys (HEAs) matrix composites were prepared by induction melting method. With increasing NbC content, the strength of the composites increases first and decreases afterwards, while the ductility decreases monotonically. The composite with 5 vol% NbC exhibits an excellent combination of yield strength (458.9 MPa), ultimate tensile strength (917.9 MPa), and ductility (29.0% elongation). The enhanced strength of the composite can be attributed to the synergy of various strengthening mechanisms, including dislocation strengthening, Orowan strengthening and load-bearing effect. Density functional theory (DFT) calculations revealed that the addition of NbC particles increases the value at Fermi level for individual elements in the HEA matrix, which provides support for improving mechanical properties of the NbC-reinforced composites. [Display omitted] •Submicron-sized NbC particles played a key role in performance enhancement.•The optimal composite presented an excellent combination of strength and ductility.•The mechanical properties were discussed from the view of DOS for the first time.