Insight into the structure and tribological and corrosion performance of high entropy (CrNbSiTiZr)C films: First-principles and experimental study
By Wang, Junjun; Zhang, Honglin; Yu, Xu; Wang, Linqing; Huang, Weijiu; Lu, Zhibin
Published in Surface and Coatings Technology
2021
Abstract
The formation possibility of high-entropy alloy (CrNbSiTiZr)C was first studied by analyzing thermodynamics parameters through first-principles calculation. Then, the (CrNbSiTiZr)C film was successfully deposited by reactive radio frequency magnetron sputtering. Theoretical analysis results show that the mixing enthalpy and entropy values of (CrNbSiTiZr)C were 18.45 kJ/mol and 0.805 R, respectively, indicating that (CrNbSiTiZr)C is thermodynamically stable above the temperature of 2758 K. Experimental results show that the concentration of each metal element in the film is near an equimolar ratio and a mixture of Cr3C2, NbC, SiC, TiC, ZrC, and oxide formed in the (CrNbSiTiZr)C film. Moreover, the as-prepared film possesses a single B1 structure with a (111) preferred orientation and exhibits high nanohardness, elastic modulus, and fracture toughness. The friction coefficients and wear rate of the (CrNbSiTiZr)C film is as low as 0.3 and 4.2 × 10−6 mm3/N·m, respectively. The film also shows a superior corrosion resistance in a 3.5 wt% NaCl solution, a positive Ecorr and a low icorr value of −189 mV and 0.0026 μA/cm2, respectively. The film is proposed for industrial applications given its excellent mechanical, tribology, and corrosion performance and based on the theoretical analysis and experiment results.