The corrosion behaviour of Mg-3.0Nd-0.4Zr (NK30) magnesium alloy was investigated in as-cast (F), solution treated (T4) and peak-aged (T6) conditions in 5% NaCl solution by immersion tests and electrochemical measurem...The corrosion behaviour of Mg-3.0Nd-0.4Zr (NK30) magnesium alloy was investigated in as-cast (F), solution treated (T4) and peak-aged (T6) conditions in 5% NaCl solution by immersion tests and electrochemical measurements. The results of immersion test show that NK30 alloy exhibits better corrosion resistance in F condition than it does in the other two conditions due to the more compact corrosion film formed on alloy in F condition. The potentiodynamic polarization curves show that the overpotential of cathodic hydrogen evolution reaction on NK30-F is much higher than that on NK30-T4 and NK30-T6. The corrosion potentials of NK30 increase in the following order: F<T4<T6. The results of electrochemical impedance spectroscopy (EIS) also confirm that the corrosion film of NK30-F plays a more protective role than that of NK30-T4 and NK30-T6.展开更多
The effect of plastic deformation prior to artificial aging on the aging characteristics and mechanical properties of a Mg-11Gd-2Nd-0.5Zr (mass fraction, %) alloy was investigated. After solution treatment at 525 ℃ f...The effect of plastic deformation prior to artificial aging on the aging characteristics and mechanical properties of a Mg-11Gd-2Nd-0.5Zr (mass fraction, %) alloy was investigated. After solution treatment at 525 ℃ for 4 h, the alloy was subjected to cold stretching deformation of 0%, 5% and 10%, respectively. The as-deformed specimens possess high density of dislocations and mechanical twins, which increase with elevated deformation. As compared with non-stretched alloy, the stretched alloy shows accelerated age-hardening response and slightly enhanced peak hardness when aged at 200 ℃. Comparison of the microstructures in undeformed and deformed specimens after 200 ℃, 24 h aging reveals that pre-deformation induces the heterogeneous nucleation of precipitations at dislocations and twin boundaries in addition to the homogeneous precipitation in the matrix. Room and high temperature tensile test results show that pre-deformation enhances the strength of the alloy, especially at room temperature, though the ductility declines. The improvement in strength of deformed and aged alloy is attributed to the combined strengthening effect of precipitates, deformation structures and grain boundaries.展开更多
基金Project(5133003C) supported by the Major State Basic Research Development Program of China
文摘The corrosion behaviour of Mg-3.0Nd-0.4Zr (NK30) magnesium alloy was investigated in as-cast (F), solution treated (T4) and peak-aged (T6) conditions in 5% NaCl solution by immersion tests and electrochemical measurements. The results of immersion test show that NK30 alloy exhibits better corrosion resistance in F condition than it does in the other two conditions due to the more compact corrosion film formed on alloy in F condition. The potentiodynamic polarization curves show that the overpotential of cathodic hydrogen evolution reaction on NK30-F is much higher than that on NK30-T4 and NK30-T6. The corrosion potentials of NK30 increase in the following order: F<T4<T6. The results of electrochemical impedance spectroscopy (EIS) also confirm that the corrosion film of NK30-F plays a more protective role than that of NK30-T4 and NK30-T6.
文摘The effect of plastic deformation prior to artificial aging on the aging characteristics and mechanical properties of a Mg-11Gd-2Nd-0.5Zr (mass fraction, %) alloy was investigated. After solution treatment at 525 ℃ for 4 h, the alloy was subjected to cold stretching deformation of 0%, 5% and 10%, respectively. The as-deformed specimens possess high density of dislocations and mechanical twins, which increase with elevated deformation. As compared with non-stretched alloy, the stretched alloy shows accelerated age-hardening response and slightly enhanced peak hardness when aged at 200 ℃. Comparison of the microstructures in undeformed and deformed specimens after 200 ℃, 24 h aging reveals that pre-deformation induces the heterogeneous nucleation of precipitations at dislocations and twin boundaries in addition to the homogeneous precipitation in the matrix. Room and high temperature tensile test results show that pre-deformation enhances the strength of the alloy, especially at room temperature, though the ductility declines. The improvement in strength of deformed and aged alloy is attributed to the combined strengthening effect of precipitates, deformation structures and grain boundaries.
基金supported by the SJTU-GM Collaborative Research Laboratory Jointly Established by General Motors Global Research and Development(GM R&D)Research was Supported by National Key Research and Development Program of China(2016YFB0301000)+2 种基金Shanghai Rising-Star Program(15QB1402700)National Natural Science Foundation of China(NSFC)(51671128&51771113)Special Fund of Jiangsu Province(BA2016039).
基金supported by National Natural Science Foundation of China(Nos.51975146,52205344)the Natural Science Foundation of Shandong Province,China(No.ZR2020QE171)+1 种基金the Key Research and Development Plan in Shandong Province,China(No.2019JZZY010364)the National Defense Basic Scientific Research of China(No.JCK2018603C017)。
