Ternary mixture of Cu, Mg, and Ni with the nominal composition of nanocrystalline Cu (XRD) 50Mg and 25 Ni transmission 25 (in at.%) was electron milled microscopy for 25 hours.(TEM) Analysis was used of an to X‐ray characterize diffraction the pattern chemical phases and microstructure of the final product, which is shown to consist of ternary alloy of Cu-Mg-Ni with FCC structure along with small amounts of FCC MgO and Mg attributed 0.85 Cu0. 15 to. The good the formation agreement between the size values obtained by XRD and TEM is of defect‐free grains with no substructure during ball milling. Dynamic recrystallization may be a possible mechanism for the emergence of such small grains (< 20 nm). The particle size distribution and morphological changes of Cu–Mg–Ni powders were also analyzed by scanning electron microscopy (SEM). According to the SEM results, the particle size of the powders decreased with increasing milling time. Lattice parameter of the Cu‐Mg‐Ni ternary FCC alloy formed during mechanical alloying increased with increase in milling time from 3.61 to 3.65 Å after 20 hours milling.