We synthesized Ti25Ni25Fe25Co25 and Ti20Ni20Fe20Co20Cu20 high entropy alloys using the mechanical alloying and spark plasma sintering (MA+SPS) method and examined their microstructural, mechanical, and tribological properties. The analysis revealed that the matrix structure comprises an FCC solid solution and C14 laves intermetallics. In the comparison of TiNiFeCo and TiNiFeCoCu samples, the mechanical characteristics diminished due to the presence of Cu in the TiNiFeCoCu alloy. The Vickers microhardness of the TiNiFeCo sample increased by ~ 43%, nanohardness by ~ 157%, and Young's modulus by ~ 24% compared to the TiNiFeCoCu sample. The TiNiFeCo sample exhibited a reduced coefficient of friction (COF) and superior wear resistance compared to the TiNiFeCoCu sample. The yield strength and tensile strength of the TiNiFeCo sample rose by 53% and 31%, respectively, compared …
