Enhancing the Corrosion Resistance of Al–Cu–Li Alloys through Regulating Precipitation

The influences of aging treatments on microstructures and the corrosion properties of an Al–Cu–Li alloy were investigated through an immersion test in intergranular corrosion (IGC) solutions, a potentiodynamic polarization test, and electrochemical impedance spectra (EIS), combined with scanning and transmission electron microscopy. The results demonstrated that the Al–Cu–Li alloy displayed outstanding comprehensive mechanical properties and IGC resistance after treating with pre-strain deformation and a double aging process (PDA). Both the PDA and pre-strain followed by creep aging (PCA) treatments significantly increased the number densities of T1 and θ’ precipitates in the grain interior. The increase in precipitates in the grain interior greatly reduced the Cu-rich precipitates on the grain boundaries and inhibited the formation of a precipitate-free zone (PFZ). The electrochemical characteristics of the Al–Cu–Li alloy were influenced by the precipitates in the grain interior and grain boundaries. The studied alloy gained high IGC resistance due to the refinement of its microstructure, and the main corrosion mode was intra-granular pitting corrosion; thus, the corrosion diffusion rate was slowed down.

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Performance of Ba0.5Sr0.5Co0.8Fe0.2O3-δ-Ag Composite Cathode Materials for IT-SOFCs

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.311-313.2309 ◽

2011 ◽

Vol 311-313 ◽

pp. 2309-2314 ◽

Cited By ~ 2

Author(s):

Wen Xia Zhu ◽

Zhe Lü ◽

Le Xin Wang ◽

Xiao Yan Guan ◽

Xin Yan Zhang

Keyword(s):

Solid Oxide Fuel Cells ◽

Electrochemical Impedance ◽

Composite Cathode ◽

Solid Oxide ◽

Electrode Polarization ◽

Impedance Spectra ◽

Electrochemical Impedance Spectra ◽

Composite Cathodes ◽

Reduced Temperature ◽

Resistance Value

°Abstract. In order to develop new cathodes for reduced temperature SOFCs, Ba0.5Sr0.5Co0.8Fe0.2O3-δ-Ag composite cathode was investigated in intermediate-temperature Solid Oxide Fuel Cells (IT-SOFCs). The XRD results suggested that no chemical reactions between BSCF and Ag in the composite cathode were found. The resistance measurements showed that the addition of Ag into BSCF improved electrical conductivity of pure BSCF, and the improved conductivity resulted in attractive cathode performance. In addition, electrochemical impedance spectra exhibited the better performance of BSCF-Ag composite cathodes than pure BSCF, e.g., the polarization resistance value of BSCF-Ag was only 0.36Ω cm2 at 650°C, which was nearly 80% lower than that of BSCF electrode. Polarization curves showed the overpotential decreased with the addition of Ag. The current density value of BSCF-Ag was 0.88Acm-2 under –120mV, about five times of that BSCF measured at 650°C. As a summary, compared to a pure BSCF cathode, it was found that adding Ag in the cathode enhanced the BSCF performance significantly.

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Interaction between Sodium Molybdate and FSWed Wled of 5083 Effected by Time

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.699.645 ◽

2013 ◽

Vol 699 ◽

pp. 645-649

Author(s):

Chang Bin Shen

Keyword(s):

Inhibition Efficiency ◽

Electrochemical Impedance ◽

Electrochemical Corrosion ◽

Sodium Molybdate ◽

Impedance Spectra ◽

Electrochemical Impedance Spectra ◽

Friction Stir ◽

Base Materials ◽

Corrosion Behaviors ◽

5083 Aluminum Alloy

Similar welds composed of 5083 were produced by friction stir welding. In the solution of 0.2 M NaHSO3 and 0.6 M NaCl, with the addition of a given concentration sodium molybdate as the inhibitor, the electrochemical corrosion behaviors of the friction stir welds (FSW) and 5083 were comparatively investigated by potentiodynamic polarization curve tests and electrochemical impedance spectra (EIS) at the ambient temperature for different test periods. The results indicated that : with the extension of period, the inhibition efficiencies (IE) for both the weld and 5083 base materials enhanced, at the same period, the inhibition efficiency (IE) for the weld was beyond that for 5083 base materials, sodium molybdate may be thought of as an effective inhibitor for 5083 aluminum alloy, the interaction between inhibitor and weld is stronger than that between inhibitor and base materials.

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An analysis of drifts and nonlinearities in electrochemical impedance spectra

Electrochimica Acta ◽

10.1016/j.electacta.2011.06.112 ◽

2011 ◽

Vol 56 (22) ◽

pp. 7467-7475 ◽

Cited By ~ 9

Author(s):

Niket S. Kaisare ◽

Vimala Ramani ◽

Karthik Pushpavanam ◽

S. Ramanathan

Keyword(s):

Electrochemical Impedance ◽

Impedance Spectra ◽

Electrochemical Impedance Spectra

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Few-Layered MoS2 Nanostructures for Highly Efficient Visible Light Photocatalysis

NANO ◽

10.1142/s1793292016501149 ◽

2016 ◽

Vol 11 (10) ◽

pp. 1650114 ◽

Cited By ~ 5

Author(s):

Dan Li ◽

Jianwei Li ◽

Caiqin Han ◽

Xinsheng Zhao ◽

Haipeng Chu ◽

...

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Visible Light ◽

Electrochemical Impedance ◽

X Ray Diffraction ◽

Electron Hole ◽

Electrochemical Impedance Spectra ◽

X Ray ◽

Transmission Electron ◽

Electron Hole Pair

Few-layered MoS2 nanostructures were successfully synthesized by a simple hydrothermal method without the addition of any catalysts or surfactants. Their morphology, structure and photocatalytic activity were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, electrochemical impedance spectra and UV-Vis absorption spectroscopy, respectively. These results show that the MoS2 nanostructures synthesized at 180[Formula: see text]C exhibit an optimal visible light photocatalytic activity (99%) in the degradation of Rhodamine B owing to the relatively easier adsorption of pollutants, higher visible light absorption and lower electron–hole pair recombination.

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