The corrosion behavior of 5A05 aluminum alloy in 3.5 wt.% NaCl solution was investigated by scanning electron microscopy（SEM）, X-ray photoelectron spectroscopy（XPS）, Fourier transform-infrared（FT-IR） spectroscop...The corrosion behavior of 5A05 aluminum alloy in 3.5 wt.% NaCl solution was investigated by scanning electron microscopy（SEM）, X-ray photoelectron spectroscopy（XPS）, Fourier transform-infrared（FT-IR） spectroscopy and electrochemical impedance spectroscopy（EIS） test, and the corrosion mechanism was also discussed. The results showed that the corrosion rates of the 5A05 alloy were low and decreased with the increase in immersion time. Under the conditions of exposure studied, this alloy sufered from pitting corrosion that took place from or around the intermetallic particles existing in the alloy. The number and size of the hemispherical corrosion pits on the sample surfaces increased with the increase of the test time. The dark-grey layer of corrosion products formed on 5A05 aluminum alloy in 3.5% NaCl solution contained many microcracks. Furthermore, XPS and FT-IR analysis proved that the corrosion products were mainly composed of Al2 O3, Al（OH）3 and AlCl3.展开更多
Galvanic corrosion on samples of AZ91D magnesium alloy coupled with 2A12 aluminum alloy during neutral salt spray test was investigated.The variations of the surface potential were measured using scanning kelvin probe...Galvanic corrosion on samples of AZ91D magnesium alloy coupled with 2A12 aluminum alloy during neutral salt spray test was investigated.The variations of the surface potential were measured using scanning kelvin probe（SKP）.The results showed that galvanic effect on the corrosion of AZ91D magnesium alloy is closely related to the potential difference between the anodic and cathodic materials.In the initial period,corrosion only occurred in a narrow area at the coupling interface because of the limited distance galvanic current.Then,the corrosion rate of 2A12 aluminum alloy was accelerated due to its poor stability in strong alkali environment,which was attributed to the strong alkalization caused by the corrosion of AZ91D magnesium alloy.With the increase of the potential of 2A12 aluminum alloy as a result of the continuous covering of corrosion products,the potential difference between the two materials was enlarged,which enhanced the galvanic corrosion.展开更多
文摘The corrosion behavior of 5A05 aluminum alloy in 3.5 wt.% NaCl solution was investigated by scanning electron microscopy（SEM）, X-ray photoelectron spectroscopy（XPS）, Fourier transform-infrared（FT-IR） spectroscopy and electrochemical impedance spectroscopy（EIS） test, and the corrosion mechanism was also discussed. The results showed that the corrosion rates of the 5A05 alloy were low and decreased with the increase in immersion time. Under the conditions of exposure studied, this alloy sufered from pitting corrosion that took place from or around the intermetallic particles existing in the alloy. The number and size of the hemispherical corrosion pits on the sample surfaces increased with the increase of the test time. The dark-grey layer of corrosion products formed on 5A05 aluminum alloy in 3.5% NaCl solution contained many microcracks. Furthermore, XPS and FT-IR analysis proved that the corrosion products were mainly composed of Al2 O3, Al（OH）3 and AlCl3.
基金Funded by the National Natural Science Foundation of China(No.51271032)
文摘Galvanic corrosion on samples of AZ91D magnesium alloy coupled with 2A12 aluminum alloy during neutral salt spray test was investigated.The variations of the surface potential were measured using scanning kelvin probe（SKP）.The results showed that galvanic effect on the corrosion of AZ91D magnesium alloy is closely related to the potential difference between the anodic and cathodic materials.In the initial period,corrosion only occurred in a narrow area at the coupling interface because of the limited distance galvanic current.Then,the corrosion rate of 2A12 aluminum alloy was accelerated due to its poor stability in strong alkali environment,which was attributed to the strong alkalization caused by the corrosion of AZ91D magnesium alloy.With the increase of the potential of 2A12 aluminum alloy as a result of the continuous covering of corrosion products,the potential difference between the two materials was enlarged,which enhanced the galvanic corrosion.
