Stress Corrosion Cracking in an Extruded Cu-Free Al-Zn-Mg Alloy

Metals

Lars Lodgaard¹  Roy Johnsen²  John C. Walmsley³  Randi Holmestad³  Adrian Lervik³  Otto Lunder⁴  Calin D. Marioara⁴ 

[1] Benteler Automotive, 2830 Raufoss, Norway;Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway;Department of Physics, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway;SINTEF Industry, N-7465 Trondheim, Norway;

关键词: aluminium alloys;    stress corrosion cracking;    transmission electron microscopy;    EBSD;    microstructure;    grain boundaries;   

DOI  :  10.3390/met10091194

来源: DOAJ

【 摘 要 】

Stress corrosion cracking (SCC) in Cu-free Al-Zn-Mg (7xxx) aluminium alloys limits its use in many applications. In this work, we study in detail the microstructure of a peak and slightly overaged condition in an AA7003 alloy using transmission- and scanning electron microscopy in order to provide a comprehensive understanding of the microstructural features related to SCC. The SCC properties have been assessed using the double cantilever beam method and slow strain rate tensile tests. Grain boundary particles, precipitate free zones, and matrix precipitates have been studied. A difference in the SCC properties is established between the two ageing conditions. The dominating difference is the size and orientation of the hardening phases. Possible explanations correlating the microstructure and SCC properties are discussed.

【 授权许可】

Unknown