Microstructural characteristics of large-scale ultrafine-grained copper

Large-scale production of ultrafine-grained copper was prepared by the spark plasma sintering (SPS) method. The densification behavior and the microstructural characteristics of the bulk compact were investigated; mechanical tests demonstrate that both the strength and the elongation were improved due to the fine grain size. Four typical microstructures were found, the sintering mechanism was studied by dividing the sintering process into 4 stages according to the evolution of the microstructure.