scholarly journals The Influence of Sodium Tungstate Concentration on the Electrode Reactions at Iron–Tungsten Alloy Electrodeposition

Coatings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 981
Author(s):  
Stanislav Belevskii ◽  
Serghei Silkin ◽  
Natalia Tsyntsaru ◽  
Henrikas Cesiulis ◽  
Alexandr Dikusar
Keyword(s):  
Rotating Disk ◽  
Electrochemical Quartz Crystal Microbalance ◽  
Rotating Disk Electrode ◽  
Tungsten Alloy ◽  
Alloy Formation ◽  
Health Issues ◽  
Cathodic Current ◽  
Alloy Electrodeposition ◽  
Electrode Reactions ◽  
And Diffusion

The investigation of Fe-W alloys is growing in comparison to other W alloys with iron group metals due to the environmental and health issues linked to Ni and Co materials. The influence of Na2WO4 concentration in the range 0 to 0.5 M on bath chemistry and electrode reactions on Pt in Fe-W alloys’ electrodeposition from citrate electrolyte was investigated by means of rotating disk electrode (RDE) and cyclic voltammetry (CV) synchronized with electrochemical quartz crystal microbalance (EQCM). Depending on species distribution, the formation of Fe-W alloys becomes thermodynamically possible at potentials less than −0.87 V to −0.82 V (vs. Ag/AgCl). The decrease in electrode mass during cathodic current pass in the course of CV recording was detected by EQCM and explained. The overall electrode process involving Fe-W alloy formation may be described using formalities of mixed kinetics. The apparent values of kinetic and diffusion currents linearly depend on the concentration of Na2WO4. Based on the values of partial currents for Fe and W, it was concluded that codeposition of Fe-W alloy is occurring due to an autocatalytic reaction, likely via the formation of mixed adsorbed species containing Fe and W compounds or nucleation clusters containing both metals on the electrode surface.

Manufacturing Technology of μ-Gear and Mold by Fe-Ni Alloy Electroforming

2011 ◽  
Vol 291-294 ◽  
pp. 3032-3035
Author(s):  
Seong Ho Son ◽  
Won Sik Lee ◽  
Hong Kee Lee ◽  
Hyun Jong Kim ◽  
Sung Cheol Park
Keyword(s):  
Chemical Reaction ◽  
Reaction Rate ◽  
High Hardness ◽  
Rotating Disk ◽  
Rotating Disk Electrode ◽  
Powder Injection ◽  
Alloy Electrodeposition ◽  
Temperature Range ◽  
Good Surface ◽  
Ni Alloy

The micro parts were fabricated by electroforming process of Fe-Ni alloy. Reaction mechanism of Fe-Ni alloy electrodeposition process was investigated using rotating disk electrode. To clarify the rate determining step, the activation energies of iron and nickel elements were calculated from the Arrhenius plot in the temperature range of 308K~328K. The reaction rate of iron in electrodeposition of Fe-Ni alloy was controlled by chemical reaction at temperature range of 308K~318K, while at range of 318K~328K, it was controlled by mass transport. The reaction rate of nickel was controlled by chemical reaction at 308K~318K and by a mixed mechanism of chemical reaction and mass transfer at 318K~328K. For alloy electroforming of micro gears and a mold for powder injection molding, the mandrels of micro gear (1.7mm in diameter and 600 μm in height) and micro mold (550 μm in diameter and 600 μm in height) were prepared by UV-lithography using SU-8 photoresist. Subsequently, Fe-Ni alloy micro gear mold were electroformed with high hardness (490 Hv) and very good surface roughness (Ra 37.5 nm).

Fabrication and Characterization of Nife Thin Film Composition Modulated Alloys

1996 ◽  
Vol 451 ◽  
Author(s):  
S. D. Leith ◽  
D. T. Schwartz
Keyword(s):  
Rotation Rate ◽  
Stripping Voltammetry ◽  
Rotating Disk ◽  
Oscillation Period ◽  
Rotating Disk Electrode ◽  
Disk Rotation ◽  
Rate Oscillation ◽  
Composition And Structure ◽  
Spatially Periodic

ABSTRACTDescribed are results showing that an oscillating flow-field can induce spatially periodic composition variations in electrodeposited NiFe films. Flow-induced NiFe composition modulated alloys (CMA's) were deposited on the disk of a rotating disk electrode by oscillating the disk rotation rate during galvanostatic plating. Deposit composition and structure were investigated using potentiostatic stripping voltammetry and scanning probe microscopy. Results illustrate a linear relationship between the composition modulation wavelength and the flow oscillation period. CMA's with wavelengths less than 10 nm can be fabricated when plating with a disk rotation rate oscillation period less than 3 seconds.

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