Recently, there are more researchers investigated the mechanical properties of the HEAFs with nitrogen incorporation due to superior properties like high hardness. As above-mentioned, nitride-based HEAFs can be synthesized via magnetron sputtering by incorporating N 2 and Ar gases into the vacuum chamber. Adjusting the nitrogen flow ratio, R N = N 2 /(Ar + N 2), can obtain different amounts of nitrogen. Most of them increased the nitrogen flow ratio to study the correlation between phase transformation and mechanical properties.