Atom probe tomographic study of elemental segregation at grain boundaries for a peak-aged Al–Zn–Mg alloy

• DOI: 10.1016/j.corsci.2013.10.027
• Publication Date: 2013-11-01T18:04:37Z
• Authors: X.Y. Sun; B. Zhang; H.Q. Lin; Y. Zhou; L. Sun; J.Q. Wang; E.-H. Han; W. Ke
• Keywords: 0103 physical sciences; 01 natural sciences

Abstract Atom probe tomography (APT) has been used to characterize the element segregation at the grain boundary (GB) for a peak-aged Al–Zn–Mg alloy with high stress corrosion cracking (SCC) susceptibility. The results show that Mg segregates along the GB with a peak concentration of 1.38 at.% and width of 3 nm. Zn does not segregate at GB. However, segregation of Zn and H atoms at oxide-containing clusters on GB has been observed. APT atom maps also reveal that Mg 2 Si is the H trapping site, but MgZn 2 is not.