The effects of 0.01 wt.%Ga on microstructure and electrochemical performance of Al−0.4Mg−0.05Sn−0.03Hg anodes in NaOH solutions were investigated.Potentiodynamic polarization,electrochemical impedance spectroscopy,and...The effects of 0.01 wt.%Ga on microstructure and electrochemical performance of Al−0.4Mg−0.05Sn−0.03Hg anodes in NaOH solutions were investigated.Potentiodynamic polarization,electrochemical impedance spectroscopy,and galvanostatic discharge tests were used to assess the electrochemical performance of the Al−Mg−Sn−Hg−Ga anodes.The results show that the addition of 0.01 wt.%Ga in Al−0.4Mg−0.05Sn−0.03Hg anode enhances its corrosion resistance and discharge activity.It is benefited from the refined second phases and homogenous microstructure of Al−Mg−Sn−Hg−Ga anode,which restrains the local crystallographic corrosion and chunk effect.Compared with Al−Mg−Sn−Hg anode,the corrosion current density and the mass loss rate of Al−Mg−Sn−Hg−Ga anode decrease by 57%and 93%,respectively.When discharging at the current density of 20 mA/cm^(2),the discharge voltage,current efficiency and specific capacity of the single Al−air battery with Al−0.4Mg−0.05Sn−0.03Hg−0.01Ga anode are 1.46 V,33.1%,and 1019.2 A·h·kg^(−1),respectively.The activation mechanism of Ga on Al−Mg−Sn−Hg−Ga anode materials was also discussed.展开更多
This paper presents the research on the atmospheric corrosion rates of carbon steel, zinc and copper in Chongqing, which was a corrosion subprogram of an international project, Regional Air Pollution in Developing Cou...This paper presents the research on the atmospheric corrosion rates of carbon steel, zinc and copper in Chongqing, which was a corrosion subprogram of an international project, Regional Air Pollution in Developing Countries. We performed field exposure tests of carbon steel, zinc and copper at an urban site Guanyinqiao and a rural site Tieshanping inChongqing, then used grey relational analysis, based on the database of the whole corrosion project, to determine the order of the effect of environmental factors on corrosion rates of tested metals, and established dose-response functions for these three metals. The results showed that the two crucial agents of acidic environment, SO2 and H+, were common factors that contributed most to the corrosion of the tested metals. The established dose-response functions for outdoor carbon steel and zinc are proved applicable to use in Chongqing, but the function for copper needs further modifying. We employed these dose- response functions and general environmental data to elaborate the maps of corrosion rate respectively of carbon steel and zinc by geological information system (GIS) technique which help to identify areas of high corrosion damage risk. An acceptable annual average SO2 level of 21 μg/m3 for carbon steel and that of 61 μg/m3 for zinc are also put forward to control the air pollution impact on atmospheric corrosion in Chongqing urban areas.展开更多
基金This work is supported by the Equipment Pre-research Laboratory Foundation in Central South University,China(No.6142912200104).
文摘The effects of 0.01 wt.%Ga on microstructure and electrochemical performance of Al−0.4Mg−0.05Sn−0.03Hg anodes in NaOH solutions were investigated.Potentiodynamic polarization,electrochemical impedance spectroscopy,and galvanostatic discharge tests were used to assess the electrochemical performance of the Al−Mg−Sn−Hg−Ga anodes.The results show that the addition of 0.01 wt.%Ga in Al−0.4Mg−0.05Sn−0.03Hg anode enhances its corrosion resistance and discharge activity.It is benefited from the refined second phases and homogenous microstructure of Al−Mg−Sn−Hg−Ga anode,which restrains the local crystallographic corrosion and chunk effect.Compared with Al−Mg−Sn−Hg anode,the corrosion current density and the mass loss rate of Al−Mg−Sn−Hg−Ga anode decrease by 57%and 93%,respectively.When discharging at the current density of 20 mA/cm^(2),the discharge voltage,current efficiency and specific capacity of the single Al−air battery with Al−0.4Mg−0.05Sn−0.03Hg−0.01Ga anode are 1.46 V,33.1%,and 1019.2 A·h·kg^(−1),respectively.The activation mechanism of Ga on Al−Mg−Sn−Hg−Ga anode materials was also discussed.
基金a corrosion subprogram of the international project Regional Air Pollution in Developing Countries under the contract No. JT73065.
文摘This paper presents the research on the atmospheric corrosion rates of carbon steel, zinc and copper in Chongqing, which was a corrosion subprogram of an international project, Regional Air Pollution in Developing Countries. We performed field exposure tests of carbon steel, zinc and copper at an urban site Guanyinqiao and a rural site Tieshanping inChongqing, then used grey relational analysis, based on the database of the whole corrosion project, to determine the order of the effect of environmental factors on corrosion rates of tested metals, and established dose-response functions for these three metals. The results showed that the two crucial agents of acidic environment, SO2 and H+, were common factors that contributed most to the corrosion of the tested metals. The established dose-response functions for outdoor carbon steel and zinc are proved applicable to use in Chongqing, but the function for copper needs further modifying. We employed these dose- response functions and general environmental data to elaborate the maps of corrosion rate respectively of carbon steel and zinc by geological information system (GIS) technique which help to identify areas of high corrosion damage risk. An acceptable annual average SO2 level of 21 μg/m3 for carbon steel and that of 61 μg/m3 for zinc are also put forward to control the air pollution impact on atmospheric corrosion in Chongqing urban areas.
