340An AlMgFeCuCrNi based high entropy alloy was synthesized by mechanical alloying. Phase analysis at room temperature was investigated by using X-ray diffraction. It has been found that two phase solid-solution with body-centered cubic (BCC) and face-centered cubic (FCC) crystal structure forms in this alloy system. Damping capacity of powder samples was determined using dynamic mechanical analysis. Effect of sintering at different temperatures, such as 800°C, 850°C, and 900°C, on phase evolution and hardness was investigated.