Enhancing wear resistance: In-situ ceramic phase precipitation for strengthening and toughening FeCoNiCrNx high-entropy alloy films

• Published in: Surface & coatings technology 2024-02, Vol.478, p.130466, Article 130466
• Main Authors: Liu, W., Wang, C.T., Zhao, S.C., Chen, L., Li, Y.T., Jiang, X., Leng, Y.X.
• Format: Article
• Language: English
• Subjects: FeCoCrNi; High entropy alloy film; Nanocomposite structure; Reactive magnetron sputtering; Wear resistance
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2024.130466

FeCoNiCr high-entropy alloys have attracted widespread attention because of their excellent toughness; however, their insufficient hardness limits their application in wear-resistant films. The introduction of non-metallic elements is an effective method for strengthening high entropy alloys films. In this study, high-entropy alloy films of FeCoNiCrNx with varying nitrogen content were fabricated using reactive magnetron sputtering. The influence of nitrogen content on the structure, mechanical properties, and tribological behavior of these high-entropy alloy films was studied. With an increase in nitrogen content, the FeCoNiCrNx film undergoes amorphization and simultaneous precipitation of Cr2N phases. At lower nitrogen flow rates (0–4 sccm), the film exhibits lower hardness (8.51–10.97 GPa) and poor wear resistance. At moderate nitrogen flow rates (8 sccm), the film exhibits enhanced hardness (12.8 GPa) and toughness, leading to favorable wear resistance (4.04 × 10−6 mm3 N−1 m−1). A further increase in the nitrogen flow rates (12–16 sccm), while raising hardness (13.08–15.17 GPa), leads to a slight reduction in toughness and consequently, a mild decrease in wear resistance (4.37–5.09 × 10−6 mm3 N−1 m−1). A biphase structure design combining FeCoNiCr high entropy alloy and ceramic (Cr2N) improved the strength and toughness of FeCoNiCrNx and significantly enhanced its wear resistance, thus enhancing its application potential. •A strength-toughness integrated FeCoNiCrNx film with a composite structure was prepared.•The effect of nitrogen content on the structure and properties of high-entropy alloy films was investigated.•The wear resistance of the film has seen a significant enhancement after the addition of nitrogen atoms.