Formation of nanophases in a Cu-Zn alloy under high current density electropulsing

The microstructure of samples before and after a high current density elect ropulsing treatment was characterized by using high-resolution transmission electron microscopy. It has been found that in the coarse-grained Cu-Zn al loy subjected to the electropulsing treatment, two nanophases were formed, alpha-Cu(Zn) and beta'-(CuZn), the average grain size of which is about II nm. A possible mechanism for the formation of nanophases was proposed. The experimental results indicated that electropulsing, as an instantaneous hig h-energy input, plays an important role in the nonequilibrium microstructur al changes in materials and serves as a potential processing approach to sy nthesize nanostructured materials.