Effect of B Content on Mechanical Properties and Corrosion Resistance of (TiZrNbMoTa)B _x C High‐Entropy Alloy Coatings

(TiZrNbMoTa)B _x C high‐entropy alloys coatings have been fabricated by magnetron sputtering and the effects of B content on microstructure, mechanical properties, and corrosion behavior have been systematically investigated. The results indicate that the coatings exhibit a single‐phase face‐centered cubic structure. The addition of B forms reinforcing solid‐solution borides, thus strengthening and hardening the coating. When the B target power is 100 W, the coating hardness can reach 31.22 GPa, the elasticity modulus is 345.82 GPa, and the wear rate reached 9.82 × 10 ⁻⁵ mm ³ /(N·m). As the B target power rises 200 W, the corrosion current density of the (TiZrNbMoTa)B _x C coating in 3.5% NaCl solution decreased from the initial 4.06 × 10 ⁻⁶ to 5.26 × 10 ⁻⁷ A/cm ² . This was mainly attributed to the addition of B, which enhanced the repair of the passivation film of (Borides) and effectively slowed down the corrosion process. This work is about the effect of B doping on the mechanical and corrosion resistance of (TiZrNbMoTa)B _x C coatings, providing theoretical support for improving the surface wear and corrosion resistance of engineering materials.