In the present work,the effects of neodymium(Nd)on micro structure,mechanical performance,and corrosion behavior of powder metallurgy Mg-2Si-xNd(x=0.05 wt%,0.15 wt%,and 0.20 wt%)alloys were investigated.Microstructure...In the present work,the effects of neodymium(Nd)on micro structure,mechanical performance,and corrosion behavior of powder metallurgy Mg-2Si-xNd(x=0.05 wt%,0.15 wt%,and 0.20 wt%)alloys were investigated.Microstructures were examined by optical and scanning electron microscopes combined with an energy-dispersive spectrometer.Hardness and compressive tests were used to study the mechanical properties of alloys.Potentiodynamic polarization,electrochemical impedance spectroscopy(EIS),Mott-Schottky analysis,and the hydrogen evolution test were applied to characterize the corrosion behavior of alloys in Hanks'solution.The microstructure of Mg-2Si-xNd alloys mainly consists ofα-Mg matrix,Mg2Si,and MgNd phases.The increase in Nd content tends to decrease the aspect ratio ofα-Mg grains,which leads to the enhancement of the ultimate-compressive strengths and hardness of the alloys.Potentiodynamic polarization shows that increasing Nd content leads to a lower corrosion current density in the Mg-2Si-xNd alloys.The EIS results confirm that a higher addition of Nd suppresses the dissolution kinetics of the alloys due to the increasing charge transfer resistance.Mott-Schottky analysis reveals the formation of an n-type semiconductive passive film on the alloy surfaces,where the interstitial and oxygen vacancies predominate over the metal vacancies.The X-ray photoelectron spectroscopy(XPS)reveals that a mixture of Mg(OH)_(2),MgO,MgCO_(3),and Nd_(2)O_(3)has formed as the corrosion products on the Mg-2Si-xNd alloy surfaces after a longer immersion time in Hanks'solution.展开更多
基金Project supported by National Research and Innovation Agency of the Republic of Indonesia(Badan Riset dan Inovasi Nasional-BRIN)through the Grant of Rumah Program Organisasi Riset Nanoteknologi dan Material(RP-ORNM)No.20/Ⅲ.10/HK/2024。
文摘In the present work,the effects of neodymium(Nd)on micro structure,mechanical performance,and corrosion behavior of powder metallurgy Mg-2Si-xNd(x=0.05 wt%,0.15 wt%,and 0.20 wt%)alloys were investigated.Microstructures were examined by optical and scanning electron microscopes combined with an energy-dispersive spectrometer.Hardness and compressive tests were used to study the mechanical properties of alloys.Potentiodynamic polarization,electrochemical impedance spectroscopy(EIS),Mott-Schottky analysis,and the hydrogen evolution test were applied to characterize the corrosion behavior of alloys in Hanks'solution.The microstructure of Mg-2Si-xNd alloys mainly consists ofα-Mg matrix,Mg2Si,and MgNd phases.The increase in Nd content tends to decrease the aspect ratio ofα-Mg grains,which leads to the enhancement of the ultimate-compressive strengths and hardness of the alloys.Potentiodynamic polarization shows that increasing Nd content leads to a lower corrosion current density in the Mg-2Si-xNd alloys.The EIS results confirm that a higher addition of Nd suppresses the dissolution kinetics of the alloys due to the increasing charge transfer resistance.Mott-Schottky analysis reveals the formation of an n-type semiconductive passive film on the alloy surfaces,where the interstitial and oxygen vacancies predominate over the metal vacancies.The X-ray photoelectron spectroscopy(XPS)reveals that a mixture of Mg(OH)_(2),MgO,MgCO_(3),and Nd_(2)O_(3)has formed as the corrosion products on the Mg-2Si-xNd alloy surfaces after a longer immersion time in Hanks'solution.
