Phase decomposition in nanocrystalline Cr0.8Cu0.2 thin films

•APT results confirm onset of phase decomposition in the as-deposited Cr0.8Cu0.2 thin film by spinodal decomposition.•XRD and APT results confirm formation of metastable Cr0.6Cu0.4 precipitates during early stage of phase decomposition.•Annealing temperature ≥400 °C leads to formation of two-phase structure (fcc Cu(Cr) + bcc Cr(Cu)).•Phase decomposition is accompanied by significant change in the films stresses and crystallographic textures.•Possibility of non-classical nucleation of metastable Cr0.6Cu0.4 precipitates has been explored.