Grain boundary diffusion and segregation of 57Co in high-purity copper: Radiotracer measurements in B- and C-type diffusion regimes. (1st April 2017)

• Record Type: Journal Article
• Authors: Gaertner, Daniel; Wilde, Gerhard; Divinski, Sergiy V.
• Is Part Of: Acta materialia. Volume 127(2017)
• Page Start: 407
• Page End: 415
• Publication Date: 2017-04-01
• Subjects: Copper -- Grain boundary diffusion -- Grain boundary segregation -- Cobalt; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2017.01.045
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: Grain boundary diffusion of 57 Co in high-purity polycrystalline copper is investigated using the radiotracer technique in Harrison's B- (850–1150 K) and C-type (550–950 K) kinetic regimes. The triple product P = s · δ · D gb ( s is the segregation factor and δ the grain boundary width) and the grain boundary diffusion coefficient D gb of Co in Cu are determined to obey the Arrhenius laws with the activation enthalpies of Q gb = 66.2 kJ/mol and H gb = 100.9 kJ/mol, respectively. Using the experimental estimate of δ, δ ≅ 0.5 nm, Co is found to segregate strongly at Cu grain boundaries and the corresponding segregation factor follows an Arrhenius dependence with the segregation enthalpy of H s = −34.7 kJ/mol. Co-diffusion experiments with the 57 Co and 110m Ag isotopes support a 'sub-interface'-type of grain boundary segregation of Co in Cu. Graphical abstract: Image 1