TY - JOUR
T1 - Unexpected Stress Corrosion Cracking Improvement Achieved by Recrystallized Layer in Al-Zn-Mg Alloy
AU - Ao, Min
AU - Dong, Chaofang
AU - Li, Ni
AU - Wang, Li
AU - Ji, Yucheng
AU - Yue, Liang
AU - Sun, Xiaoguang
AU - Zou, Shiwen
AU - Xiao, Kui
AU - Li, Xiaogang
N1 - Publisher Copyright:
© 2021, ASM International.
PY - 2021/8
Y1 - 2021/8
N2 - To explore the correlation between the stress corrosion sensitivity and formation processing for high-strength Al-Zn-Mg alloy, extrusion surface and the matrix were investigated by microstructural characterizations, electrochemistry, and stress corrosion cracking (SCC) tests. Larger, but with low density and discontinuity, grain boundary precipitates (GBPs, − 60 nm and − 3.7% area fraction) and intermetallic particles (IMPs, − 0.5% area fraction) were achieved in the secondary recrystallized (SR) coarse-grained layer compared with the non-recrystallized matrix. The maximum Volta potential differences between the IMPs and Al matrix were about 373 mV, causing the pitting initiation by micro-galvanic effect. The decreased pitting density and the low residual stress in the SR layer reduced the available initiation sites for SCC. Thus, the SR layer acted as a barrier layer to reduce the SCC susceptibility of the extruded Al-Zn-Mg alloy in Cl−-containing environments.
AB - To explore the correlation between the stress corrosion sensitivity and formation processing for high-strength Al-Zn-Mg alloy, extrusion surface and the matrix were investigated by microstructural characterizations, electrochemistry, and stress corrosion cracking (SCC) tests. Larger, but with low density and discontinuity, grain boundary precipitates (GBPs, − 60 nm and − 3.7% area fraction) and intermetallic particles (IMPs, − 0.5% area fraction) were achieved in the secondary recrystallized (SR) coarse-grained layer compared with the non-recrystallized matrix. The maximum Volta potential differences between the IMPs and Al matrix were about 373 mV, causing the pitting initiation by micro-galvanic effect. The decreased pitting density and the low residual stress in the SR layer reduced the available initiation sites for SCC. Thus, the SR layer acted as a barrier layer to reduce the SCC susceptibility of the extruded Al-Zn-Mg alloy in Cl−-containing environments.
KW - Al-Zn-Mg alloy
KW - intermetallic phase
KW - precipitate
KW - secondary recrystallized layer
KW - stress corrosion cracking
UR - https://www.scopus.com/pages/publications/85106530108
U2 - 10.1007/s11665-021-05856-4
DO - 10.1007/s11665-021-05856-4
M3 - 文章
AN - SCOPUS:85106530108
SN - 1059-9495
VL - 30
SP - 6258
EP - 6268
JO - Journal of Materials Engineering and Performance
JF - Journal of Materials Engineering and Performance
IS - 8
ER -