• Bulletin of the Korean Chemical Society
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• v.22 no.9
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• pp.994-998
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• 2001

Ni, Fe and NiFe alloy thin films were electrodeposited at a polycrystalline Au surface using a range of electrolytes and potentials. Coulometry and EQCM were used for real-time monitoring of electroplating efficiency of the Ni and Fe. The plating efficiency of NiFe alloy thin films was computed with the aid of ICP spectrometry. In general, plating efficiency increased to a steady value with deposition time. Plating efficiency of Fe was lower than that of Ni at -0.85 and -1.0 V but the efficiency approached to the similar plateau value to that of Ni at more negative potentials. The films with higher content of Fe showed different stripping behavior from the ones with higher content of Ni. Finally, compositional data and real-time plating efficiency are presented for films electrodeposited using a range of electrolytes and potentials.

• Journal of the Korea Convergence Society
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• v.8 no.11
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• pp.307-312
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• 2017

In the industry, galvanizing using the principle of sacrificial anode is used Zn-Ni alloy plating was developed as one of the measures to increase the corrosion resistance rather than pure zinc plating. The alloy plating layer has a corrosion resistance of 4-5 times that of the pure zinc plating layer, so that it is applied to automotive parts requiring high corrosion resistance even though the plating cost is high. The amount of Zn-Ni alloy plating solution is a sulfuric acid bath, a chlorinated bath, an alkali bath, and an ammonia bath. Here, the influence of the electrolytic conditions on the composition of the alloy plating in the chloride bath was investigated. The results are explained by the cathode overvoltage and the diffusion coefficient. In general, as the overvoltage of the cathode increases, the concentration polarization becomes more important than the activation polarization. The concentration polarization is determined by element diffusion in the diffusion layer. That is, as the overvoltage of the cathode increases, the Zn content having a large diffusion coefficient increases.

• Journal of Surface Science and Engineering
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• v.35 no.3
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• pp.141-148
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• 2002

Fe-C alloy layers were produced by pulse plating and the properties were compared with those produced by D.C. plating. When the pulse on time ($T_{on}$ ) was the same, both the duty cycle and peak current density($I_{p}$ ) had little influence on the carbon content and the hardness of the layer. The structure and hardness of the direct current plating were similar to those of the pulse current plating. However, the ductility was enhanced when the pulse current was applied due to the release of residual stress during the pulse off time($T_{off}$).).

• Corrosion Science and Technology
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• v.18 no.5
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• pp.190-195
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• 2019

SA508 low-alloy steel for a reactor vessel was exposed to primary water in a pressurized water reactor (PWR) plant because the cladding layer of type 309 stainless steel for the RPV was removed, due to an accident in which the detachment of the thermal sleeve occurred. The major advantage of the electrochemical deposition (ECD) Ni plating technique is that the reactor pressure vessel can be repaired without significant thermal effects, and Ni has solid corrosion resistance that can withstand boric acid. The corrosion rate assessment of the damaged part was performed, and its trend was analyzed. Essential variables of the Ni plating for repair of the damaged part were derived. These conditions are applicable variables for the repair plating device, and have been carefully adjusted using the repair plating device. The process for establishing ASME technical standards called Code Case N-840 is described. The process of developing Ni-plating devices, and the electroplating procedure specification (EPS) are described.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.67-72
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• 1999

Optimal pretreatment processes for metal plating on engineering plastics, especially on Nylon-inorganic filler alloy was studied. For Nylon-inorganic filler alloy, adhesion strength between resin surface and metal could be improved by just etching process that eliminate amorphous layer. In the SEM picture and surface roughness measurement, etching treatment was found to make enabled the surface condition very rough and the adhesion strength good. It was also found that the surface condition of plated article and its adhesion strength partly depended upon molding condition of Nylon-inorganic filler alloy. EDS, peaks showed that what kinds of and how much of the metal elements remained on the resin surface after pretreatment processes. Cr did not affect on adsorption of Sn and Pd remarkably.

• Journal of Surface Science and Engineering
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• v.46 no.5
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• pp.208-215
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• 2013

The aim of the present study was to improve the radiative heat dissipation of aluminum alloy, Al 1050. Resin/CuO coating and Cu/CuO composite plating were applied on aluminum alloy to improve the radiative heat dissipation. Resin/CuO coating was made using thermosetting silicon resin and Cu/CuO composite plating was made in pyrophosphate copper plating bath. Radiant heat flux($W/m^2$) was measured by self-produced radiant heat measurement device to compare each specimen. The cross section of specimen and chemical bonding of surface were analyzed by FE-SEM, XPS and FT-IR. As a result, radiant heat of Resin/CuO coating was higher than Cu/CuO composite plating due to the adhesion with aluminum plate and the difference in chemical bonding. But, Both of them were higher than aluminum alloy. In order to confirm the result of experiment, aluminum plate, Resin/CuO coating and Cu/CuO composite plating sample were applied LED and measured the LED temperature. As a result, LED temperature of samples were matched previous results and confirmed coated samples were lower about 10 degrees than the aluminum alloy.

• Journal of Hydrogen and New Energy
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• v.3 no.2
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• pp.9-15
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• 1992

Electroless copper plating method using an alkaline bath have been employed in copper coating of the (LM)Ni4.5Co0.1MnO.2A10.2 hydrogen storage alloy powders for electrode preparation. The plating were conducted without any pretreatment of alloy powders. For the preparation of the electrodes, about 0.12g of the copper coated alloy powder (copper to alloy ratio 1/3 by weight) was compacted with pressure of 6 tons/cm2 at room temperature. The disk-type compacts had a diameter of 10mm and thickness of about 0.24mm. The electrode characteristics were examined through SEM observations and electrochemical measurements in a half cell. The electrochemical measurement showed that the maximum discharge capacity of the electrodes prepared by using alkaline bath were 245mAh per gram of coated alloy (327mAh per gram of alloy) and appeared a considerable degradation with increasing number of cycles. The decrease of the discharge capacity after 100 cycles was about 30% It can be suggested that, with a slight of improvement, this electroless copper plating method could be applied to the preparation of the rare earth-nickel based alloy electrode.

• Journal of Surface Science and Engineering
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• v.21 no.1
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• pp.19-27
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• 1988

The principe and practice of pulse plating, and prospect in the future on pulse plating are reviewed. Some of the advantages of pulse pulse plating are detailed as compared with DC plating. The advantages of pulse plating are summarized as follows: 1)smooth and fine grained deposits 2) reduction in hydrogen embrittlement of deposits 3) reduction of residual stress and microcracks in the deposit 4) improvement of physical properties 5) uniform alloy composition through the deposit thinkness 6) improved thrower and adhesion.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.285-286
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• 2006

Magnesium is the lightest of all the structural metals having density of 1.74. It is approximately 2/3 lighter than aluminium, l/4 lighter than titanium alloy and 1/5 lighter than iron. Among the light-weight alloys, magnesium and its alloys show a good possibility for high performance aerospace and automotive applications, however the widespread use of magnesium alloys has been limited mainly by its poor oxidation and corrosion resistance. In this work, corrosion-resistive thin films were prepared onto the magnesium alloy substrate(AZ91D) by environmental friendly coating technique, ion plating method. And their corrosion protection mechanism were analyzed.

• Journal of Surface Science and Engineering
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• v.55 no.5
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• pp.299-307
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• 2022

Gold plating is used as a coating of connector in printed circuit boards, ceramic integrated circuit packages, semiconductor devices and so on, because the film has excellent electric conductivity, solderability and chemical properties such as durability to acid and other chemicals. In most cases, internal connection between device and package and external terminals for connecting packaging and printed circuit board are electroless Ni-P plating followed by immersion Au plating (ENIG) to ensure connection reliability. The deposition behavior and film properties of electroless Au plating are affected by P content, grain size and mixed impurity components in the electroless Ni-P alloy film used as the underlayer plating. In this study, the correlation between electroless nickel plating used as a underlayer layer and cyanide-free electroless Au plating using thiomalic acid as a complexing agent and aminoethanethiol as a reducing agent was investigated.