Smooth and compact nickel layers were successfully prepared in the ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate(BMIMBF4)by constant current electrodeposition method.The effects of temperature,additive...Smooth and compact nickel layers were successfully prepared in the ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate(BMIMBF4)by constant current electrodeposition method.The effects of temperature,additive content,current density,and deposition time on the performance of the nickel layers were systematically analyzed.Scanning electron microscopy(SEM)and X-ray diffraction(XRD)were used to analyze the surface morphology and composition of the nickel layers.Meanwhile,the tensile strengths of the nickel layers were tested by universal tensile testing machine.The results show that different process conditions have a great effect on morphology and performance of the electrodeposited nickel layer.The optimization of process parameters is as follows:BMIMBF4 to ethylene glycol(EG)volume ratio of 2:1,deposition temperature of 120℃,and current density of 1.2 mA·cm^(-2).Current density has a greater influence on the tensile strength of the nickel layer,and the maximum value of tensile strength is 1275 MPa.展开更多
In order to prepare electroformed nickel with excellent properties,the effect of different waveforms on microstructure and mechanical properties was investigated by optical microscopy(OM),X-ray diffraction(XRD) and te...In order to prepare electroformed nickel with excellent properties,the effect of different waveforms on microstructure and mechanical properties was investigated by optical microscopy(OM),X-ray diffraction(XRD) and tensile test,respectively.The results show that the samples are composed of micron columnar grains with high-density nanoscale coherent twin boundaries which are parallel to the growth plane.The tensile strength and elongation display opposite tendency with the increase in current density when direct current(DC) electroforming was applied.However,under the condition of pulse current(unidirectional,bidirectional) electroforming,the change regulation of tensile strength and elongation is close while cathode(peak,positive peak) current density increases.XRD results show that electroformed nickel layers with high purity are all fcc crystal configuration under different conditions of the current waveform.The nickel layers formed under bidirectional pulse current behave superior global performance with tensile strength of 692.0 MPa and elongation of 27.6 %.展开更多
Molybdenum is a kind of refractory metal and can hardly be deposited in aqueous solution since it is more likely to form molybdenum oxide rather than elementary Mo,but molten salts and ionic liquid become alternative ...Molybdenum is a kind of refractory metal and can hardly be deposited in aqueous solution since it is more likely to form molybdenum oxide rather than elementary Mo,but molten salts and ionic liquid become alternative to obtain Mo layer.This paper shows an available process to obtain metallic state molybdenum deposit from ionic liquid.Mo layer was electrodeposited under constant current in ionic liquid 1-Butyl-3-methylimidazolium tetrafluoroborate(BMIMBF_4).Micromorphology of the electrodeposited Mo layer was observed by scanning electron microscope(SEM),energy dispersive spectroscopy(EDS)and X-ray photoelectron spectroscopy(XPS).Results show that elementary Mo layer was electrodeposited under constant current in ionic liquid BMIMBF4.Properties of the Mo layer are affected significantly by additive ethylene glycol(EG),deposition temperature and current density.By parallel tests taking into consideration of different technical factors,optimized process parameters are obtained as volume ratio of 2:1 in BMIMBF4+EG system,deposition temperature of 150℃and current density of 0.75 mA·cm^(-2).展开更多
基金financially supported by the National Aerospace Science Foundation of China(No.2012ZE51058)。
文摘Smooth and compact nickel layers were successfully prepared in the ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate(BMIMBF4)by constant current electrodeposition method.The effects of temperature,additive content,current density,and deposition time on the performance of the nickel layers were systematically analyzed.Scanning electron microscopy(SEM)and X-ray diffraction(XRD)were used to analyze the surface morphology and composition of the nickel layers.Meanwhile,the tensile strengths of the nickel layers were tested by universal tensile testing machine.The results show that different process conditions have a great effect on morphology and performance of the electrodeposited nickel layer.The optimization of process parameters is as follows:BMIMBF4 to ethylene glycol(EG)volume ratio of 2:1,deposition temperature of 120℃,and current density of 1.2 mA·cm^(-2).Current density has a greater influence on the tensile strength of the nickel layer,and the maximum value of tensile strength is 1275 MPa.
基金financially supported by the Aviation Science Foundation,China (No.2012ZE51058)。
文摘In order to prepare electroformed nickel with excellent properties,the effect of different waveforms on microstructure and mechanical properties was investigated by optical microscopy(OM),X-ray diffraction(XRD) and tensile test,respectively.The results show that the samples are composed of micron columnar grains with high-density nanoscale coherent twin boundaries which are parallel to the growth plane.The tensile strength and elongation display opposite tendency with the increase in current density when direct current(DC) electroforming was applied.However,under the condition of pulse current(unidirectional,bidirectional) electroforming,the change regulation of tensile strength and elongation is close while cathode(peak,positive peak) current density increases.XRD results show that electroformed nickel layers with high purity are all fcc crystal configuration under different conditions of the current waveform.The nickel layers formed under bidirectional pulse current behave superior global performance with tensile strength of 692.0 MPa and elongation of 27.6 %.
基金financially supported by the Aeronautical Science Foundation of China(No.2012ZE51058)。
文摘Molybdenum is a kind of refractory metal and can hardly be deposited in aqueous solution since it is more likely to form molybdenum oxide rather than elementary Mo,but molten salts and ionic liquid become alternative to obtain Mo layer.This paper shows an available process to obtain metallic state molybdenum deposit from ionic liquid.Mo layer was electrodeposited under constant current in ionic liquid 1-Butyl-3-methylimidazolium tetrafluoroborate(BMIMBF_4).Micromorphology of the electrodeposited Mo layer was observed by scanning electron microscope(SEM),energy dispersive spectroscopy(EDS)and X-ray photoelectron spectroscopy(XPS).Results show that elementary Mo layer was electrodeposited under constant current in ionic liquid BMIMBF4.Properties of the Mo layer are affected significantly by additive ethylene glycol(EG),deposition temperature and current density.By parallel tests taking into consideration of different technical factors,optimized process parameters are obtained as volume ratio of 2:1 in BMIMBF4+EG system,deposition temperature of 150℃and current density of 0.75 mA·cm^(-2).
