JOURNAL OF ALLOYS AND COMPOUNDS, cilt.1020, 2025 (SCI-Expanded)
This study focused on developing cost-effective FeMnCoCr(Mo) high-entropy alloy thin films (HEATFs) through magnetron sputtering. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analyses revealed that the films exhibited an amorphous-nanocrystalline FCC structure with nanosized-columnar features, contributing to their mechanical properties. Nanoindentation tests demonstrated that incorporating Mo significantly increased both hardness and elastic modulus, with values rising from 6.9 GPa and 133 GPa for Mo-free films to 8.95 GPa and 215 GPa for Mo-doped films. This improvement is attributed to solid-solution strengthening and increased lattice distortion caused by Mo. However, the addition of Mo reduced the H/E and H3/E2 ratios, indicating a trade-off between increased hardness and reduced elasticity. This suggests that while Mo enhances strength, it may also increase coating stiffness, potentially affecting wear resistance in certain applications. The findings highlight the importance of balancing hardness and elasticity, along with microstructural control, to optimize the mechanical performance of HEATFs for industrial applications.