Mg-6%Al-5%Pb and Mg-6%Al-5%Pb-0.55%Zn-0.22%Mn(mass fraction) alloys were prepared by induction melting with the protection of argon.The corrosion behaviors of these alloys were studied by electrochemical measurements ...Mg-6%Al-5%Pb and Mg-6%Al-5%Pb-0.55%Zn-0.22%Mn(mass fraction) alloys were prepared by induction melting with the protection of argon.The corrosion behaviors of these alloys were studied by electrochemical measurements and immersion tests.The results show that at the corrosion onset of Mg-Al-Pb anode there is an incubation period that can be shortened with 0.55%Zn and 0.22%Mn additions in the magnesium matrix.The corrosion rate of Mg-Al-Pb anode is mainly determined by the incubation period.Short incubation period always leads to high corrosion rate while long incubation period leads to low corrosion rate.The corrosion rates based on the corrosion current density by the electrochemical measurements do not agree with the measurements evaluated from the evolved hydrogen volume.展开更多
The corrosion behavior of Cu-Cr alloy in 3.5%NaCl+NH3 solution had been studied, and the influences of the concentration of NH3 on corrosion resistance discussed by means of Metallograph, XRD, SEM and electrochemical ...The corrosion behavior of Cu-Cr alloy in 3.5%NaCl+NH3 solution had been studied, and the influences of the concentration of NH3 on corrosion resistance discussed by means of Metallograph, XRD, SEM and electrochemical method. The results show that the Cu is easier to corrosion than Cr, and the corrosion rate increases with the increasing of the concentration of NH3, and deformation worsen the corrosion resistance of the alloy in such corrosive environment.展开更多
Mg-6%Al-1%Sn(mass fraction) alloy is a newly developed anode material for seawater activated batteries. The electrochemical properties of Mg-1%Sn, Mg-6%Al and Mg-6%Al-1%Sn alloys are measured by galvanostatic and pote...Mg-6%Al-1%Sn(mass fraction) alloy is a newly developed anode material for seawater activated batteries. The electrochemical properties of Mg-1%Sn, Mg-6%Al and Mg-6%Al-1%Sn alloys are measured by galvanostatic and potentiodynamic tests. Scanning electron microscopy(SEM) with energy dispersive spectrometry(EDS) is used to characterize the microstructures of the experimental alloys. The results show that the Mg-6%Al-1%Sn alloy obtains more negative discharge potential(-1.38 V(vs SCE)) in hot-rolled condition. This is attributed to the fine dynamically recrystallized grains during the hot rolling process. After the experimental alloys are annealed at 473 K for 1 h, the discharge potentials of Mg-6%Al-1%Sn alloy are more negative than those of Mg-6%Al alloy under different current densities. After annealing at 673 K, the discharge potentials of Mg-6%Al-1%Sn alloy become more positive than those of Mg-6%Al alloy. Such phenomenon is due to the coarse grains and the second phase Mg2 Sn. The discharge potentials of Mg-1%Sn shift positively obviously in the discharge process compared with Mg-6%Al-1%Sn alloy. This is due to the corrosion products pasting on the discharge surface, which leads to anode polarization.展开更多
基金Project(JPPT-115-168) supported by National Key Science and Technological Project of China
文摘Mg-6%Al-5%Pb and Mg-6%Al-5%Pb-0.55%Zn-0.22%Mn(mass fraction) alloys were prepared by induction melting with the protection of argon.The corrosion behaviors of these alloys were studied by electrochemical measurements and immersion tests.The results show that at the corrosion onset of Mg-Al-Pb anode there is an incubation period that can be shortened with 0.55%Zn and 0.22%Mn additions in the magnesium matrix.The corrosion rate of Mg-Al-Pb anode is mainly determined by the incubation period.Short incubation period always leads to high corrosion rate while long incubation period leads to low corrosion rate.The corrosion rates based on the corrosion current density by the electrochemical measurements do not agree with the measurements evaluated from the evolved hydrogen volume.
文摘The corrosion behavior of Cu-Cr alloy in 3.5%NaCl+NH3 solution had been studied, and the influences of the concentration of NH3 on corrosion resistance discussed by means of Metallograph, XRD, SEM and electrochemical method. The results show that the Cu is easier to corrosion than Cr, and the corrosion rate increases with the increasing of the concentration of NH3, and deformation worsen the corrosion resistance of the alloy in such corrosive environment.
基金supported by the Open Fund of the Sate Key Laboratory of Powder Metallurgy(Central South University),China
文摘Mg-6%Al-1%Sn(mass fraction) alloy is a newly developed anode material for seawater activated batteries. The electrochemical properties of Mg-1%Sn, Mg-6%Al and Mg-6%Al-1%Sn alloys are measured by galvanostatic and potentiodynamic tests. Scanning electron microscopy(SEM) with energy dispersive spectrometry(EDS) is used to characterize the microstructures of the experimental alloys. The results show that the Mg-6%Al-1%Sn alloy obtains more negative discharge potential(-1.38 V(vs SCE)) in hot-rolled condition. This is attributed to the fine dynamically recrystallized grains during the hot rolling process. After the experimental alloys are annealed at 473 K for 1 h, the discharge potentials of Mg-6%Al-1%Sn alloy are more negative than those of Mg-6%Al alloy under different current densities. After annealing at 673 K, the discharge potentials of Mg-6%Al-1%Sn alloy become more positive than those of Mg-6%Al alloy. Such phenomenon is due to the coarse grains and the second phase Mg2 Sn. The discharge potentials of Mg-1%Sn shift positively obviously in the discharge process compared with Mg-6%Al-1%Sn alloy. This is due to the corrosion products pasting on the discharge surface, which leads to anode polarization.
