TY - JOUR

T1 - Improving the corrosion resistance of 7055 alloy by manipulating passivation film through trace addition of TiB2 nanoparticles

AU - Li, Xuekai

AU - Wang, Wei

AU - Wu, Yihong

AU - Kang, Huijun

AU - Guo, Enyu

AU - LI, Jiehua

AU - Chen, Zongning

AU - Xu, Yanjin

AU - Wang, Tongmin

N1 - Publisher Copyright: © 2024 Elsevier B.V.

PY - 2024/5/30

Y1 - 2024/5/30

N2 - In this study, 7055 alloy inoculated by a minor addition of TiB 2 nanoparticles was prepared and subjected to passivation treatment. The microstructures, pitting behaviors, and electrochemical properties of the 7055-0.5TiB 2 composite were comparatively investigated with respect to the base alloy. The results show that the incorporation of 0.5 wt% TiB 2 nanoparticles refines the grain size (from 142.4 μm to 44.1 μm) and reduces the volume fractions of the residual intermediates from 0.59 % to 0.49 %, leading to an increased thickness (from 4.05 nm to 5.95 nm) and improved homogeneity of the passivation film. Both the pitting diameter and the pitting area fractions are reduced upon immersing in 3.5 % NaCl for 24 h. Electrochemical test results show that the values of passivation layer resistance, charge transfer resistance, and polarization resistance are significantly increased, while the corrosion current is reduced after the incorporation of TiB 2 nanoparticles, confirming the formation of a more effective barrier layer, i.e., the passivation film. The improved corrosion resistance of 7055 alloy with the incorporation of TiB 2 nanoparticles is attributed to the reduced active dissolution rate in the grain boundary region and a more uniform and thicker passivation film with a lower corrosion rate.

AB - In this study, 7055 alloy inoculated by a minor addition of TiB 2 nanoparticles was prepared and subjected to passivation treatment. The microstructures, pitting behaviors, and electrochemical properties of the 7055-0.5TiB 2 composite were comparatively investigated with respect to the base alloy. The results show that the incorporation of 0.5 wt% TiB 2 nanoparticles refines the grain size (from 142.4 μm to 44.1 μm) and reduces the volume fractions of the residual intermediates from 0.59 % to 0.49 %, leading to an increased thickness (from 4.05 nm to 5.95 nm) and improved homogeneity of the passivation film. Both the pitting diameter and the pitting area fractions are reduced upon immersing in 3.5 % NaCl for 24 h. Electrochemical test results show that the values of passivation layer resistance, charge transfer resistance, and polarization resistance are significantly increased, while the corrosion current is reduced after the incorporation of TiB 2 nanoparticles, confirming the formation of a more effective barrier layer, i.e., the passivation film. The improved corrosion resistance of 7055 alloy with the incorporation of TiB 2 nanoparticles is attributed to the reduced active dissolution rate in the grain boundary region and a more uniform and thicker passivation film with a lower corrosion rate.

KW - Aluminum matrix composite

KW - Aluminum microstructure

KW - Corrosion

KW - Passive film

UR - http://www.scopus.com/inward/record.url?scp=85185401905&partnerID=8YFLogxK

U2 - 10.1016/j.apsusc.2024.159722

DO - 10.1016/j.apsusc.2024.159722

M3 - Article

VL - 656.2024

JO - Applied surface science

JF - Applied surface science

SN - 0169-4332

IS - 30 May

M1 - 159722

ER -