Effect of added Co2 +(aq)on copper electrowinning was studied using doped polyaniline(Pani)and Pb-Ag(1%)anodes and a stainless steel cathode.The presence of added Co2+ (aq)in the electrolyte solution was found to decr...Effect of added Co2 +(aq)on copper electrowinning was studied using doped polyaniline(Pani)and Pb-Ag(1%)anodes and a stainless steel cathode.The presence of added Co2+ (aq)in the electrolyte solution was found to decrease the anode potentials.The optimum level of Co2 +(aq)concentration in the electrolyte,with respect to the maximum saving of power consumption was established.Linear sweep voltammetry(LSV)was used to study the influence of added Co2 +(aq)on the anodic processes in a copper sulfate-sulfuric acid electrolyte.The oxygen-evolution potential for Pani anode is depolarised at lower current densities(≤0.01 A/cm2)and attains saturation atρ(Co 2+ )o≈0.789 g/L;whilst the oxygen-evolution potential for Pb-Ag(1%)anode is depolarised at higher current densities(≤0.02 A/cm2)and attains saturation atρ(Co 2+ )o≈1.315 g/L.The preferred orientations of the copper deposits change from(220)to(111)with the addition of 0.394?0.789 g/L Co 2+ but higher concentrations favor(220)orientation again.展开更多
The Pb-free solders have attracted a great deal of attention recently due to the environmental concerns.The present work focuses on the effect of cobalt content(0,0.5 and 3.0)on the microstructural characteristics,mel...The Pb-free solders have attracted a great deal of attention recently due to the environmental concerns.The present work focuses on the effect of cobalt content(0,0.5 and 3.0)on the microstructural characteristics,melting point and corrosion performance of extruded Sn-9Zn solder alloys.The results reveal that the Zn-rich precipitates with spherical or needle-like shape in the Sn-9Zn-xCo alloys are refined remarkably by forming the γ-Co5Zn21 and Co2Sn2Zn Co-contained intermetallic compounds,though the melting point and eutectic reaction temperature decrease slightly.It is suggested that the corrosion property of the extruded Sn-9Zn-xCo alloys is improved significantly by adding the cobalt element,while the content should be controlled reasonably.Combining the corrosion morphology,the influence of cobalt content on the corrosion behavior of the Sn-9Zn-xCo alloys is analyzed in terms of the refined microstructure and the enhanced passive film stability.展开更多
基金Project(50974065)supported by the National Natural Science Foundation of ChinaProject(2009009)supported by the Analysis and Testing Foundation of Kunming University of Science and Technology,China
文摘Effect of added Co2 +(aq)on copper electrowinning was studied using doped polyaniline(Pani)and Pb-Ag(1%)anodes and a stainless steel cathode.The presence of added Co2+ (aq)in the electrolyte solution was found to decrease the anode potentials.The optimum level of Co2 +(aq)concentration in the electrolyte,with respect to the maximum saving of power consumption was established.Linear sweep voltammetry(LSV)was used to study the influence of added Co2 +(aq)on the anodic processes in a copper sulfate-sulfuric acid electrolyte.The oxygen-evolution potential for Pani anode is depolarised at lower current densities(≤0.01 A/cm2)and attains saturation atρ(Co 2+ )o≈0.789 g/L;whilst the oxygen-evolution potential for Pb-Ag(1%)anode is depolarised at higher current densities(≤0.02 A/cm2)and attains saturation atρ(Co 2+ )o≈1.315 g/L.The preferred orientations of the copper deposits change from(220)to(111)with the addition of 0.394?0.789 g/L Co 2+ but higher concentrations favor(220)orientation again.
基金Project(2017YFB0305700)supported by the Ministry of Science and Technology of ChinaProjects(51490660,51490664)supported by the National Natural Science Foundation of ChinaProject(2017YFB0305700)supported by the National Key Research and Development Project of China。
文摘The Pb-free solders have attracted a great deal of attention recently due to the environmental concerns.The present work focuses on the effect of cobalt content(0,0.5 and 3.0)on the microstructural characteristics,melting point and corrosion performance of extruded Sn-9Zn solder alloys.The results reveal that the Zn-rich precipitates with spherical or needle-like shape in the Sn-9Zn-xCo alloys are refined remarkably by forming the γ-Co5Zn21 and Co2Sn2Zn Co-contained intermetallic compounds,though the melting point and eutectic reaction temperature decrease slightly.It is suggested that the corrosion property of the extruded Sn-9Zn-xCo alloys is improved significantly by adding the cobalt element,while the content should be controlled reasonably.Combining the corrosion morphology,the influence of cobalt content on the corrosion behavior of the Sn-9Zn-xCo alloys is analyzed in terms of the refined microstructure and the enhanced passive film stability.
