Thermal oxidation of amorphous CuxZr1-x alloys: Role of composition-dependent thermodynamic stability

•Thermal oxidation of amorphous Cu-Zr alloys with different Cu/Zr ratios has been studied.•High-resolution AES depth profiling and cross-sectional analytic HRTEM analyses were performed.•Cu-enriched nanoparticles emerge due to localized Cu-accumulation by selective oxidation of Zr.•Microstructures of Cu-enriched nanoparticles depend on stabilities of parent alloys.•The composition-dependent microstructure of oxidized CuxZr1−x influences oxidation kinetics.