In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were system...In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were systematically studied.The results show that the coatings prepared from the phosphate electrolytes have a higher thickness and better corrosion resistance properties compared to the other electrolytes.The coatings prepared from low concentration phosphate-aluminate mixed electrolytes have slightly thinner thickness,a similar coating structure and an order of magnitude lower value of electrochemical impedance compared with phosphate electrolyte coatings.The Coatings prepared from low concentration aluminate electrolytes have the lowest thickness and the worst corrosion resistance properties which gets close to corrosion behavior of the bare AM50 under the same test conditions.Considering application,coatings prepared from single low concentration phosphate electrolytes and low concentration phosphate-aluminate electrolytes have greater potential than single low concentration aluminate coatings.However,reducing the electrolyte concentrations of coating forming ions too much has negative influence on the coating growth rate.展开更多
Magnesium alloy AZ91D was processed respectively in one, two, three and four-component electrolytes by using AC microarc oxidation technique. The corrosion resistance of AZ91D alloy was measured by electrochemical met...Magnesium alloy AZ91D was processed respectively in one, two, three and four-component electrolytes by using AC microarc oxidation technique. The corrosion resistance of AZ91D alloy was measured by electrochemical methods. The optimum electrolytes in two, three and four components were found. In four-component electrolyte composed by NaOH, NaAlOj, H2O2 and C4H4O6N32, the film formed on AZ91D alloy is smooth and compact, and has a higher corrosion resistance. The effect of the ingredients in electrolytes was discussed based on their roles in the formation of corrosion resistant film.展开更多
基金China Scholarship Council for the award of fellowship and funding(No.202006370022).
文摘In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were systematically studied.The results show that the coatings prepared from the phosphate electrolytes have a higher thickness and better corrosion resistance properties compared to the other electrolytes.The coatings prepared from low concentration phosphate-aluminate mixed electrolytes have slightly thinner thickness,a similar coating structure and an order of magnitude lower value of electrochemical impedance compared with phosphate electrolyte coatings.The Coatings prepared from low concentration aluminate electrolytes have the lowest thickness and the worst corrosion resistance properties which gets close to corrosion behavior of the bare AM50 under the same test conditions.Considering application,coatings prepared from single low concentration phosphate electrolytes and low concentration phosphate-aluminate electrolytes have greater potential than single low concentration aluminate coatings.However,reducing the electrolyte concentrations of coating forming ions too much has negative influence on the coating growth rate.
文摘Magnesium alloy AZ91D was processed respectively in one, two, three and four-component electrolytes by using AC microarc oxidation technique. The corrosion resistance of AZ91D alloy was measured by electrochemical methods. The optimum electrolytes in two, three and four components were found. In four-component electrolyte composed by NaOH, NaAlOj, H2O2 and C4H4O6N32, the film formed on AZ91D alloy is smooth and compact, and has a higher corrosion resistance. The effect of the ingredients in electrolytes was discussed based on their roles in the formation of corrosion resistant film.