An investigation of grain boundary diffusion and segregation of Ni in Cu in an electrodeposited Cu/Ni micro-multilayer system

Abstract Cu/Ni micro-multilayer films were prepared through additive-free electrodeposition. The grain boundary diffusion and the segregation of Ni in Cu were investigated, associated with many dislocations and other defects. The results show that Ni atoms significantly penetrate into Cu grain boundaries along the pipe diffusion path, and the concentration of Ni remains unchanged along the pipe diffusion path for a certain depth in the Cu layer, growing only in width. Furthermore, the interdiffusion coefficient of Ni along the Cu grain boundary was calculated to be about 1.940 (±0.82) ×10 −14  m 2 /s at 573 K for 3 h. In addition, the width of the pipe diffusion path was about 50 nm.