In this research, nanostructures High entropy alloy of CuMnNiZnAl was manufactured by mechanical alloying. For this purpose, copper, nickel, zinc, manganese and aluminum powders with atomic ratios equaled for 80 and 120 hours in three different ways of mechanical alloying. Internal structure and powdwe particales morphology change were studied using X-ray diffraction (XRD), scanning electrone microscopy (SEM) with energy resolusion X-ray analysis (EDS). Thermal behavior was carried out differential scanning calorimeter (DSC) and thermal gravimeter analysis (TG) . Also, microscopic tests, shear punches and wear test were used to investigate mechanical properties. The results of the X-ray diffraction test showed that this alloy had a solid solution with a FCC structure and a crystallite size of 10 nm after 120 hours of milling. The investigate of alloying process variables (milling speed, number of balles) on alloy manufacturing was studied. By calculating the energy in three route, it was determined that by increasing energy by 3 times the second path and by 8 times the total energy transferred to the powder in the third path, conditions for the formation of a solid solution were provided. . Also, the results of energy resolusion X-ray analysis (EDX) confirm the absence of impurities and the correctness of the chemical composition obtained with the compound in question. Parameters including melting point, mixing enthalpy change, mixing entropy change, atomic size difference, electronegativity difference and valence electron concentration of the alloy were calculated And comparison of the results with the proposed criteria for full stability of the phase in the high entropy alloys were completely consistent and predicted the formation of a solid solution FCC. The results of the DSC test indicated that Up to melting temperatureof the alloy no intermetallic compound is not formed in the alloy. Also, the behavior of thermal gravimeter analysis (TG) in this alloy showed that the alloy had a weight loss of 31.5% with increasing temperature to melting temperature. The thermodynamic study by the Mediama model in this alloy created a solid solution as the first phase of the formation of this alloy. Spark Plasma Sintering method was used to compress and prepare a bulk sample. For alloy produced by the alloying method, the amount of micro hardness was 750 HV. The ultimate shear stress and yield shear stress were 80.15MPa and 122.1Mpa, respectively. The tribological behavior of alloys produced by mechanical alloying at ambient temperature and 400 ° C was investigated by ball on disk for 1000m distance. Results showed that the wear mechanism at ambient temperature were delamination and adhesive wear at temperature of 400 . Also, the higher wear resistance of the alloy at 400 ° C was concluded. Finally, in order to compare some properties of CuMnNiZnAl alloy (such as micro hardness, yield shear stress and ultimate shear stress), the VAR method was also developed.
