Abstract

In this work, the corrosion behavior of a peak aged 6061 Al alloy was investigated through a combination of x-ray tomography and lab-scale x-ray diffraction contrast tomography (DCT). Pitting corrosion and intergranular corrosion (IGC) were both observed when the alloy was immersed in a 3.5 wt% NaCl solution. Pitting corrosion happens at the position of both Al 5 FeSi inclusions and Mg 2 Si precipitates. The intergranular corrosion is actually caused by the galvanic cell between grain boundary precipitates and the matrix. The 3D distribution of grain boundary characteristics was quantitatively analyzed by DCT and correlated with the IGC behavior. Investigations revealed that grain boundaries with misorientation angles smaller than 25° or larger than 45° exhibited stronger resistance to IGC. Grain boundaries with misorientation between 25° and 45° corroded more easily. The influences of IGC on the tensile properties and fracture mechanisms were also elucidated in this work. • The corrosion behavior of 6061 Al alloy was investigated by x-ray tomography and diffraction contrast tomography (DCT). • The pitting corrosion related with the Al 5 FeSi inclusions was revealed. • The correlation between intergranular corrosion and grain boundary characteristics was revealed.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.