Plasma electrolytic oxidation(PEO)coatings were formed on 7075 aluminum alloy in silicate-borate based electrolyte with different duty cycles.The physical and chemical properties of the PEO coatings were thoroughly in...Plasma electrolytic oxidation(PEO)coatings were formed on 7075 aluminum alloy in silicate-borate based electrolyte with different duty cycles.The physical and chemical properties of the PEO coatings were thoroughly investigated.The wearing and corrosion properties of the coatings were evaluated by wearing experiments and potentiodynamic polarization tests,respectively.The results showed that the micro-hardness of the coatings first increased and then decreased with the increasing duty cycle.As a results,the wearing resistance of the coatings first increased and then decreased with the increasing duty cycle.Composition analysis proved that the coatings were mainly composed ofα-Al_(2)O_(3)andγ-Al_(2)O_(3).The presence of wear scars on the worn surface morphology demonstrates that the three-body rolling was the main wear mechanism for coated specimen.The corrosion study showed that the coating formed in the mixed electrolyte with duty cycle of 80%showed the most superior corrosion resistance.展开更多
The Nd:TiO_(2 )PEO coatings were formed in a phosphate-based electrolyte with the addition of Nd_(2)O_(3 )under the current density of 150,200,250 and 300 m A/cm^(2).SEM results showed that the micropores decreased on...The Nd:TiO_(2 )PEO coatings were formed in a phosphate-based electrolyte with the addition of Nd_(2)O_(3 )under the current density of 150,200,250 and 300 m A/cm^(2).SEM results showed that the micropores decreased on quantity and increased on scale with the increasing current density.AFM results revealed that the roughness of the coatings increased with the increasing current density.Phase and composition analysis showed that the Nd:TiO_(2) coatings were mainly composed of anatase and rutile phase.And the anatase phase content has reached the maximum value at the current density of 250 m A/cm^(2).XPS results indicated that Ti2p spin-orbit components of the Nd:TiO_(2) coatings are shifted towards higher binding energy,compared with the pure TiO_(2) coating,suggesting that some of the Nd^(3+)ions are combined with TiO_(2) lattice and led to dislocation.Photocatalytic test showed that the photocatalytic activity of Nd:TiO_(2) coatings varied in the same pattern with the anatase content variation in Nd:TiO_(2) coatings.The photocatalytic experiment results show that the photocatalytic activity of Nd:TiO_(2) coatings can be greatly enhanced with moderate amount of Nd^(3+).However,excessive amount of Nd^(3+)does not have an effective impact on the photoctalytic activity improvement.展开更多
基金Funded by the National Natural Science Foundation of China(No.11802117)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.19KJB430024)the Science Foundation of the Jiangsu Industrial Software Engineering Research Center(No.ZK190401)。
文摘Plasma electrolytic oxidation(PEO)coatings were formed on 7075 aluminum alloy in silicate-borate based electrolyte with different duty cycles.The physical and chemical properties of the PEO coatings were thoroughly investigated.The wearing and corrosion properties of the coatings were evaluated by wearing experiments and potentiodynamic polarization tests,respectively.The results showed that the micro-hardness of the coatings first increased and then decreased with the increasing duty cycle.As a results,the wearing resistance of the coatings first increased and then decreased with the increasing duty cycle.Composition analysis proved that the coatings were mainly composed ofα-Al_(2)O_(3)andγ-Al_(2)O_(3).The presence of wear scars on the worn surface morphology demonstrates that the three-body rolling was the main wear mechanism for coated specimen.The corrosion study showed that the coating formed in the mixed electrolyte with duty cycle of 80%showed the most superior corrosion resistance.
基金Supported by the Open Project Foundation of Industrial Perception and Intelligent Manufacturing Equipment Engineering Research Center of Jiangsu Province (No. ZK220504)the Open Project Foundation of High-tech Key Laboratory of Agricultural Equipment and Intelligence of Jiangsu Province (No. MAET202104)+1 种基金the Open Project Foundation of Jiangsu Wind Power Engineering Technology Center (No. ZK220302)the Qing Lan Project of Jiangsu Province,China。
文摘The Nd:TiO_(2 )PEO coatings were formed in a phosphate-based electrolyte with the addition of Nd_(2)O_(3 )under the current density of 150,200,250 and 300 m A/cm^(2).SEM results showed that the micropores decreased on quantity and increased on scale with the increasing current density.AFM results revealed that the roughness of the coatings increased with the increasing current density.Phase and composition analysis showed that the Nd:TiO_(2) coatings were mainly composed of anatase and rutile phase.And the anatase phase content has reached the maximum value at the current density of 250 m A/cm^(2).XPS results indicated that Ti2p spin-orbit components of the Nd:TiO_(2) coatings are shifted towards higher binding energy,compared with the pure TiO_(2) coating,suggesting that some of the Nd^(3+)ions are combined with TiO_(2) lattice and led to dislocation.Photocatalytic test showed that the photocatalytic activity of Nd:TiO_(2) coatings varied in the same pattern with the anatase content variation in Nd:TiO_(2) coatings.The photocatalytic experiment results show that the photocatalytic activity of Nd:TiO_(2) coatings can be greatly enhanced with moderate amount of Nd^(3+).However,excessive amount of Nd^(3+)does not have an effective impact on the photoctalytic activity improvement.
