High-Entropy TiCrFeCoNi Alloy Coatings Synthesized by Pulsed Magnetron Sputtering and Cathodic Arc Plasma Deposition

Abstract This study investigates the structural and mechanical properties of TiCrFeCoNi high-entropy alloy coatings synthesized using pulsed magnetron sputtering (PMS) and cathodic arc plasma deposition (Arc-PVD) on 304L stainless steel, molybdenum, Armco iron, and Si(100) substrates. PMS coatings exhibited uniform amorphous structures across all conditions, with thicknesses of 580–610 nm and hardness up to 9.39 GPa. Arc-PVD coatings, with thicknesses from ~ 600 nm to > 4 µm depending on current and time, ranged from amorphous to polycrystalline; cyclic deposition promoted crystallization, forming FCC, B2, and Laves phases. Arc-PVD coatings achieved a maximum hardness of 10.40 GPa and reduced Young’s modulus ( E r ) of 203.96 GPa, while PMS coatings showed superior wear resistance at low modulation frequencies ( H / E r = 0.08; H 3 / E r 2 = 0.05 GPa). Wear resistance correlated with H / E r and H 3 / E r 2 ratios, and structural features were strongly dependent on deposition parameters and substrate type. These findings clarify the link between process conditions, substrate effects, and performance, enabling tailored HEA coatings for advanced industrial applications.