scholarly journals ELECTRIC DEPOSITION OF TIN-LEAD ALLOY BY PULSE CURRENT

2021 ◽  
pp. 86-89
Author(s):  
V. T. Fomichev ◽  
A. V. Savchenko ◽  
G. P. Gubarevich
Keyword(s):  
Current Efficiency ◽  
Alloy Composition ◽  
Pulse Current ◽  
Internal Stresses ◽  
Lead Alloy ◽  
Electric Mode ◽  
Electrolytic Resistance

The process of electrodeposition of a tin-lead alloy from hydrofluoride electrolytes by pulsating currents has been investigated. The influence of the electric mode on the alloy composition and properties of the resulting precipitates was studied: current efficiency, microhardness, specific electrolytic resistance, and internal stresses of the precipitates.

scholarly journals RESEARCH OF THE PROCESS OF DEPOSITION OF GALVANIC COPPER SEDIMENTS BY PULSE CURRENTS

2021 ◽  
pp. 81-85
Author(s):  
V. T. Fomichev ◽  
A. V. Savchenko ◽  
G. P. Gubarevich
Keyword(s):  
Current Efficiency ◽  
Copper Electrodeposition ◽  
Copper Plating ◽  
Copper Deposits ◽  
Electric Mode ◽  
Electrolytic Resistance

Research has been carried out on the process of copper electrodeposition from fluoride-hydrogen-boron electrolytes of copper plating by pulsed currents. The influence of the electric mode on the quality of the obtained copper deposits was studied: copper current efficiency, microhardness, specific electrolytic resistance, and internal voltages of the deposits.

ION BEAM (Cu–Pb–Sn) IMPLANTATION OF SURFACE LAYER OF 30ChGSN2A

2018 ◽  
Vol 25 (07) ◽  
pp. 1950011
Author(s):  
YU. M. BOROVIN ◽  
E. V. LUKYANENKO ◽  
V. V. OVCHINNIKOV ◽  
T. YU. SKAKOVA ◽  
N. V. UCHEVATKINA ◽  
...  
Keyword(s):  
Surface Layer ◽  
Elastic Stress ◽  
Ion Beam ◽  
Stress Fields ◽  
Internal Stresses ◽  
Lead Alloy ◽  
Mechanism Of Formation ◽  
Rotational Deformation ◽  
Multi Level ◽  
Copper Lead

Electron microscopy studies were conducted for the fine structure of ion-doped layer on 30ChGSN2A steel obtained by ion implantation of monotectic tin-doped copper–lead alloy Cu64Pb36[Formula: see text]Sn. Formation of a multi-level hierarchical structure was detected. The features of formation of each layer were analyzed, and it was found that the main mechanism of formation of these structures is diffusion and relaxation resulting in the occurrence of internal stresses both in the surface layer and in the sheet of 30ChGSN2A steel. Relaxation of elastic stress fields results in translational–rotational deformation forming various vortex structures.

scholarly journals The study of Zn–Co alloy coatings electrochemically deposited by pulse current

2012 ◽  
Vol 66 (5) ◽  
pp. 749-757 ◽  
Author(s):  
Jelena Bajat ◽  
Miodrag Maksimovic ◽  
Milorad Tomic ◽  
Miomir Pavlovic
Keyword(s):  
Surface Roughness ◽  
Current Efficiency ◽  
Direct Current ◽  
Current Density ◽  
Pulse Current ◽  
Pulse Plating ◽  
Cathodic Current ◽  
Average Current Density ◽  
Corrosion Stability ◽  
Average Current

The electrochemical deposition by pulse current of Zn-Co alloy coatings on steel was examined, with the aim to find out whether pulse plating could produce alloys that could offer a better corrosion protection. The influence of on-time and the average current density on the cathodic current efficiency, coating morphology, surface roughness and corrosion stability in 3% NaCl was examined. At the same Ton/Toff ratio the current efficiency was insignificantly smaller for deposition at higher average current density. It was shown that, depending on the on-time, pulse plating could produce more homogenous alloy coatings with finer morphology, as compared to deposits obtained by direct current. The surface roughness was the greatest for Zn-Co alloy coatings deposited with direct current, as compared with alloy coatings deposited with pulse current, for both examined average current densities. It was also shown that Zn-Co alloy coatings deposited by pulse current could increase the corrosion stability of Zn-Co alloy coatings on steel. Namely, alloy coatings deposited with pulse current showed higher corrosion stability, as compared with alloy coatings deposited with direct current, for almost all examined cathodic times, Ton. Alloy coatings deposited at higher average current density showed greater corrosion stability as compared with coatings deposited by pulse current at smaller average current density. It was shown that deposits obtained with pulse current and cathodic time of 10 ms had the poorest corrosion stability, for both investigated average deposition current density. Among all investigated alloy coatings the highest corrosion stability was obtained for Zn-Co alloy coatings deposited with pulsed current at higher average current density (jav = 4 A dm-2).

Electrodeposition process and composition of Zn-Cr alloy coatings

2018 ◽  
Vol 23 (2) ◽  
pp. 3-10
Author(s):  
Ewa Osuchowska ◽  
Zofia Buczko ◽  
Klaudia Olkowicz
Keyword(s):  
Surface Morphology ◽  
Current Efficiency ◽  
Direct Current ◽  
Current Density ◽  
Pulse Current ◽  
Electrodeposition Process ◽  
Cr Content ◽  
Zinc Coatings ◽  
Deposition Current Density

In the present work, the electrodeposition process of Zn-Cr alloy coatings under the conditions of direct and pulse current was discussed. Changes in the Cr content in the obtained alloy coatings, current efficiency of the process, surface morphology, structure and microhardness as a function of chromium(III) concentration in the bath to deposition, current density (direct and pulse) and solution mixing were determined. Surface morphology, structure and hardness of the obtained coatings were investigated. The Zn-Cr alloy coatings of good quality contained up to 0.25 %Cr (for direct current) and up to 9% Cr (for pulse current). The tested Zn-Cr alloy coatings obtained under pulse current conditions showed higher microhardness than the Zn-Cr coatings obtained under direct current conditions and than zinc coatings.

scholarly journals Methods to Determine the Current Efficiency in AC Electrolysis

2020 ◽  
Vol 46 (1) ◽  
pp. 343-352
Author(s):  
S. Yu. Kireev ◽  
Yu. P. Perelygin ◽  
S. N. Kireeva ◽  
M. J. Jaskula
Keyword(s):  
Current Efficiency ◽  
Double Layer ◽  
Pulse Current ◽  
Metal Deposition ◽  
Cathodic Current ◽  
Cathodic Current Efficiency ◽  
Deposition Processes ◽  
Methods Analytical ◽  
Experimental Researches

AbstractThe paper presents several methods (analytical, electromechanical and electronic) for determining the cathodic current efficiency of the metal deposition processes carried out by AC or pulse current. Based on the results of own experimental researches (for indium, cadmium, nickel, tin and zinc), the appropriate equations are given and the distribution of both faradaic and non-faradaic parts of charge (charging of the electrode double layer) is calculated.

scholarly journals Strategies to Achieve High Strength and Ductility of Pulsed Electrodeposited Nanocrystalline Co-Cu by Tuning the Deposition Parameters

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5194
Author(s):  
Killang Pratama ◽  
Christian Motz
Keyword(s):  
Tensile Strength ◽  
Current Density ◽  
Duty Cycle ◽  
Pulse Current ◽  
High Strength ◽  
Internal Stresses ◽  
Low Duty Cycle ◽  
Deposition Parameters ◽  
Pulse On Time ◽  
Strength And Ductility

Strategies to improve tensile strength and ductility of pulsed electrodeposited nanocrystalline Co-Cu were investigated. Parameters of deposition, which are pulse current density, duty cycle, and pulse-on time were adjusted to produce nanocrystalline Co-Cu deposits with different microstructures and morphologies. The most significant improvement of strength and ductility was observed at nanocrystalline Co-Cu deposited, at a low duty cycle (10%) and a low pulse-on time (0.3 ms), with a high pulse current density (1000 A/m2). Enhancement of ductility of nanocrystalline Co-Cu was also obtained through annealing at 200 °C, while annealing at 300 °C leads to strengthening of materials with reduction of ductility. In the as deposited state, tensile strength and ductility of nanocrystalline Co-Cu is strongly influenced by several factors such as concentration of Cu, grain size, and processing flaws (e.g., crystal growth border, porosity, and internal stresses), which can be controlled by adjusting the parameters of deposition. In addition, the presence of various microstructural features (e.g., spinodal and phase decomposition), as well as recovery processes induced by annealing treatments, also have a significant contribution to the tensile strength and ductility.

Some Effects of Electrolyte Flow in the Electroforming of Iron Foil

1986 ◽  
Vol 200 (2) ◽  
pp. 111-122
Author(s):  
J A McGeough ◽  
J R Thomson
Keyword(s):  
Mass Transfer ◽  
Hydrogen Embrittlement ◽  
Current Efficiency ◽  
Young Modulus ◽  
Reynolds Numbers ◽  
Internal Stresses ◽  
Iron Foil ◽  
Ferrous Chloride ◽  
Electrolyte Flow ◽  
Iron And Steel

Iron foil of approximate thickness 0.05 mm has been electroformed from an electrolyte solution, composed mainly of ferrous chloride and flowing at Reynolds numbers ranging from 1620 to 19 400. Current densities between 15 and 45 A/dm2 have been used. At low Reynolds numbers, the current efficiency for metal deposition is limited by inadequate mass transfer. As the Reynolds number is increased, the current efficiency rises to a maximum, after which the efficiency is again reduced due to excessive occurrence of a reaction involving the reduction of ferrous hydroxide to iron. The Young modulus of the material along the direction of electrolyte flow is less than the recognized value for polycrystalline iron and steel. This is because of the crystal orientation and internal stresses of the electrodeposited metal. Electrolyte flow induces hydrogen embrittlement of the foil. This condition is found to exert a greater influence than grain size on tensile strength, ductility and proof stress. Its effects can be alleviated by stress relief. The hardness is unaffected by hydrogen embrittlement, but is increased at higher Reynolds numbers, due to the formation of smaller grains. Direct heating of the cathode reduces material hardness without affecting tensile properties. The introduction of electrolyte flow raises the rate of electroforming of iron only by about 50 per cent when compared with that obtained from an unstirred electrolyte. This surprisingly small effect of flow is attributed to the slowness of the chemical reactions which have more control over the rate of deposition of iron than the rate of mass transfer.

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