Study of Reactive Diffusion in Cu/Zn Diffusion Couple

Abstract

Objective: To study the micro structure of the interfacial region of Cu/Zn diffusion couple at 250 • C and its evolution with diffusion time. Methods: The couple was prepared by a diffusion bonding technique and then annealed at 250 • C in Argon atmosphere. The micro structure resulting from diffusion reactions in the couple was studied by scanning electron microscopy and energy dispersive X-ray. Findings: Two continuous inter metallic phase layers formed at the interface between Cu and Zn metals. The formed inter metallic were ε and γ phases of the Cu-Zn system. The γ layer grew much faster than the ε layer. The growth kinetics of the γ phase layer was parabolic with a growth constant k p = (1, 9 ± 0, 02)10 −13 m 2 s −1 . Novelty: This study suggests that reactive diffusion in Cu/Zn diffusion couple occurs according to a model proposed in this paper.