This study aims to investigate the effects of heat treatment on the corrosion resistance and antimicrobial activity of Mg-Zn-Ag-xCa alloys under simulated physiological conditions.The focus of this research is to unde...This study aims to investigate the effects of heat treatment on the corrosion resistance and antimicrobial activity of Mg-Zn-Ag-xCa alloys under simulated physiological conditions.The focus of this research is to understand how to optimize the biomedical performance of the alloy by adjusting its composition,particularly its stability in simulated body fluids and its ability to counteract microbes.The corrosion behavior and antibacterial properties of silver-containing magnesium alloys with different calcium contents after solution treatment were studied.The results show that the addition of calcium affects the microstructure of the alloy,including grain refinement and the distribution of the second phase.It acts as a barrier at the microscopic scale,which helps to prevent the invasion of the corrosive agent,thereby improving the overall corrosion resistance of the material.The gradual increase in calcium initially has a positive effect on the properties of the alloy,especially in terms of corrosion resistance.However,when the calcium content increases to 1.5Ca,although the initial corrosion potential of the alloy increases,excessive calcium may lead to excessive accumulation of the second phase in the microstructure,which will have a negative impact on the long-term stability and corrosion resistance of the material.After corrosion,when the calcium content is 1.0 wt%,the surface roughness of the sample is 1.65μm,with the surface being the smoothest,and the corrosion rate is 0.25 mm·year-1.However,when the calcium content increases to 1.5 wt%,the sample exhibits the fastest corrosion rate at 0.45 mm·year-1.The antibacterial properties of magnesium alloy were optimized by adding silver.展开更多
Designing and fabricating the marine anti-corrosion materials without fluorine by superhydrophobic method is a huge challenge. In this study, an environmentally friendly composite coating was prepared by combing modif...Designing and fabricating the marine anti-corrosion materials without fluorine by superhydrophobic method is a huge challenge. In this study, an environmentally friendly composite coating was prepared by combing modified expanded graphite(EAG) with nano zinc oxide(ZnO). This coating showed superhydrophobic surface and good corrosion resistance. Fourier transform infrared spectroscopy(FITR), X-ray diffraction(XRD),and scanning electron microscopy(SEM) were used to characterize the materials in fabricating process of the coating. The properties of three composite coatings(ZnO,EAG, and EAG@ZnO) were analyzed, including surface roughness, water contact angle, corrosion resistance, selfcleaning and anti-fouling. The combination of ZnO and EAG caused a big water contact angle, leading superhydrophobic surface of the composite coatings. The electrochemical results showed that the superhydrophobic EAG@ZnO coating had a larger capacitive arc diameter and charge transfer resistance, indicating the enhanced anti-corrosion resistance. Meanwhile, the EAG@ZnO coating also showed good self-cleaning and anti-fouling performance according to solid and liquid pollutants tests.In addition, the mechanical properties and stability of the superhydrophobic EAG@ZnO coatings were evaluated by knife peeling and finger scratch tests. In summary, these superhydrophobic and anti-fouling EAG@ZnO composite coatings provide a potential application in marine corrosion and protection field.展开更多
Research on corrosion behaviour of zinc in natural sea water without and with fucoidan was carried out by potentiodynamic polarisation test and electrochemical impedance spectroscopy （EIS）. The results revealed that...Research on corrosion behaviour of zinc in natural sea water without and with fucoidan was carried out by potentiodynamic polarisation test and electrochemical impedance spectroscopy （EIS）. The results revealed that fucoidan serves as a good inhibitor for zinc in sea water. Polarisation curves suggested that corrosion potential values shifted to the positive ones after adding inhibitor and fucoidan retards anodic reaction more. Thus, fucoidan can be acted as anodic inhibitor. EIS results showed two phenomena including a charge transfer and an adsorption film. The corrosion inhibition of fucoidan was further confirmed by the scanning electron microscope （SEM） and atomic force microscope （AFM） analysis. Langmuir＇s adsorption isotherm was found the appropriate adsorption model.展开更多
The influence of marine aerobic biofilms on the corrosion of 316L stainless steel （SS） in aerated and deaerated seawater was studied by electrochemical impedance spectroscopy （EIS）, potentiodynamic polarisation cu...The influence of marine aerobic biofilms on the corrosion of 316L stainless steel （SS） in aerated and deaerated seawater was studied by electrochemical impedance spectroscopy （EIS）, potentiodynamic polarisation curves, current-potential curves and scanning electron microscopy with energy-dispersive spectroscopy （SEM-EDS）. EIS and SEM-EDS results showed that the aero- bic biofilms inhibited 316L SS corrosion within the test duration. Comparison of results under aerated and deaerated conditions revealed that 02 enhanced the inhibition efficiency of the aerobic biofilms. This result indicated that living cells were necessary for the aerobic biofilms to inhibit the corrosion of 316L SS. Polarization curves indicated that the biofilms mainly inhibited anode ac- tion. Current-potential curves under deaerated conditions showed that electron transfer processes occurred between microorganisms and electrodes. Moreover, 316L SS as an electron acceptor was protected from corrosion.展开更多
基金supported by Wenhai Program of the S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(No.2021WHZZB2301)Hainan Provincial Joint Project of Sanya Yazhou Bay Science and Technology City(No.2021CXLH0005)Overseas Science and Education Centers of Bureau of International Cooperation Chinese Academy of Sciences(No.121311KYSB20210005-2).
文摘This study aims to investigate the effects of heat treatment on the corrosion resistance and antimicrobial activity of Mg-Zn-Ag-xCa alloys under simulated physiological conditions.The focus of this research is to understand how to optimize the biomedical performance of the alloy by adjusting its composition,particularly its stability in simulated body fluids and its ability to counteract microbes.The corrosion behavior and antibacterial properties of silver-containing magnesium alloys with different calcium contents after solution treatment were studied.The results show that the addition of calcium affects the microstructure of the alloy,including grain refinement and the distribution of the second phase.It acts as a barrier at the microscopic scale,which helps to prevent the invasion of the corrosive agent,thereby improving the overall corrosion resistance of the material.The gradual increase in calcium initially has a positive effect on the properties of the alloy,especially in terms of corrosion resistance.However,when the calcium content increases to 1.5Ca,although the initial corrosion potential of the alloy increases,excessive calcium may lead to excessive accumulation of the second phase in the microstructure,which will have a negative impact on the long-term stability and corrosion resistance of the material.After corrosion,when the calcium content is 1.0 wt%,the surface roughness of the sample is 1.65μm,with the surface being the smoothest,and the corrosion rate is 0.25 mm·year-1.However,when the calcium content increases to 1.5 wt%,the sample exhibits the fastest corrosion rate at 0.45 mm·year-1.The antibacterial properties of magnesium alloy were optimized by adding silver.
基金financially supported by Hainan Province Science and Technology Special Fund (No. ZDYF2021GXJS210)Hainan Provincial Joint Project of Sanya Yazhou Bay Science and Technology City (No. 2021CXLH0005)+2 种基金Wenhai Program of the S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology (No. 2021WHZZB2301)Overseas Science and Education Centers of Bureau of International Cooperation Chinese Academy of Sciences (No. 121311KYSB20210005)Hainan Institute for Chinese Development Strategy of Engineering & Technology (No. 22-HN-XZ-02) and for providing support。
文摘Designing and fabricating the marine anti-corrosion materials without fluorine by superhydrophobic method is a huge challenge. In this study, an environmentally friendly composite coating was prepared by combing modified expanded graphite(EAG) with nano zinc oxide(ZnO). This coating showed superhydrophobic surface and good corrosion resistance. Fourier transform infrared spectroscopy(FITR), X-ray diffraction(XRD),and scanning electron microscopy(SEM) were used to characterize the materials in fabricating process of the coating. The properties of three composite coatings(ZnO,EAG, and EAG@ZnO) were analyzed, including surface roughness, water contact angle, corrosion resistance, selfcleaning and anti-fouling. The combination of ZnO and EAG caused a big water contact angle, leading superhydrophobic surface of the composite coatings. The electrochemical results showed that the superhydrophobic EAG@ZnO coating had a larger capacitive arc diameter and charge transfer resistance, indicating the enhanced anti-corrosion resistance. Meanwhile, the EAG@ZnO coating also showed good self-cleaning and anti-fouling performance according to solid and liquid pollutants tests.In addition, the mechanical properties and stability of the superhydrophobic EAG@ZnO coatings were evaluated by knife peeling and finger scratch tests. In summary, these superhydrophobic and anti-fouling EAG@ZnO composite coatings provide a potential application in marine corrosion and protection field.
基金supported by the National Natural Science Foundation of China(Nos.41376003 and 41006054)the National Basic Research Program of China(No.2014CB643304)
文摘Research on corrosion behaviour of zinc in natural sea water without and with fucoidan was carried out by potentiodynamic polarisation test and electrochemical impedance spectroscopy （EIS）. The results revealed that fucoidan serves as a good inhibitor for zinc in sea water. Polarisation curves suggested that corrosion potential values shifted to the positive ones after adding inhibitor and fucoidan retards anodic reaction more. Thus, fucoidan can be acted as anodic inhibitor. EIS results showed two phenomena including a charge transfer and an adsorption film. The corrosion inhibition of fucoidan was further confirmed by the scanning electron microscope （SEM） and atomic force microscope （AFM） analysis. Langmuir＇s adsorption isotherm was found the appropriate adsorption model.
基金Sponsored by National Basic Research Program(973 Program)of China(2014CB643304,2014CB643305)National Natural Science Foundation of China(51131008)The Open Fund of Key Laboratory of Marine Environmental Corrosion and Bio-fouling,Institute of Oceanology,Chinese Academy of Sciences(CKF201409)
文摘The influence of marine aerobic biofilms on the corrosion of 316L stainless steel （SS） in aerated and deaerated seawater was studied by electrochemical impedance spectroscopy （EIS）, potentiodynamic polarisation curves, current-potential curves and scanning electron microscopy with energy-dispersive spectroscopy （SEM-EDS）. EIS and SEM-EDS results showed that the aero- bic biofilms inhibited 316L SS corrosion within the test duration. Comparison of results under aerated and deaerated conditions revealed that 02 enhanced the inhibition efficiency of the aerobic biofilms. This result indicated that living cells were necessary for the aerobic biofilms to inhibit the corrosion of 316L SS. Polarization curves indicated that the biofilms mainly inhibited anode ac- tion. Current-potential curves under deaerated conditions showed that electron transfer processes occurred between microorganisms and electrodes. Moreover, 316L SS as an electron acceptor was protected from corrosion.
