Effect of Zr addition on microstructural evolution and mechanical properties of deformed and annealed Cu–Fe alloys

The influence of Zr addition on the microstructural evolution, recrystallization behavior, and mechanical properties of Cu–Fe alloys was investigated. Addition of 1 wt% Zr led to formation of Fe₂Zr and ZrO₂ phases; this process resulted in grain refinement and increased dislocation density. These precipitates effectively hindered dislocation motion and contributed to strengthening mechanisms. Zr addition significantly increased the yield strength and ultimate tensile strength across a wide range of annealing temperature T_ANN. The strengthening contributions from grain-boundary refinement, work hardening, and precipitation were substantially increased, so the alloy was strengthened by ∼141.71 MPa at T_ANN = 400 °C. Additionally, at elevated T_ANN, Zr suppressed recrystallization of the Cu phase while accelerating that of the Fe phase, so the mechanical properties varied with T_ANN. These results provide new insights to guide design of high-strength, thermally stable Cu–Fe alloys for advanced structural and electronic applications.