Effect of Aging Process on Microstructure and Properties of Cu-Ni-Al Alloy Fabricated via Spark Plasma Sintering

This study investigates the effect of aging treatment on the microstructure and properties of a Cu-10.19Ni-1.56Al (wt.%) alloy fabricated by spark plasma sintering (SPS). The results show that aging at 500 °C for 8 h yields a peak hardness of 240 HV, attributed to the precipitation of nanoscale γ'-Ni 3 Al. Electrical conductivity increases with aging temperature and time, reaching 13.7%IACS at 600 °C for 8 h due to solute depletion in the matrix. The alloy exhibits a softening temperature range of 640-670 °C and excellent thermal stability, with only an 8.2% hardness reduction after 48 h at 500 ℃. These findings demonstrate that optimized aging enables a synergistic enhancement of hardness, conductivity, and high-temperature stability through balanced precipitation strengthening and matrix purification.