• Journal of the Korean institute of surface engineering
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• v.32 no.3
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• pp.331-335
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• 1999

Electroless plating nickel has superior mechanical property to electroplated nickel. Furthermore nickel can be coated on nonconducting substrate. In this research, electroless plating of nickel were conducted in different bath condition to find optimum conditions of electroless nickel plating for MEMS applications. The selectivity of activation method on several substrates was investigated. The effects of nickel concentration, reducing agent concentration and inhibitor on deposition rate were investigated. The effect of pH on deposition rate and content of phosphorous in deposited nickel was also investigated.

• Textile Coloration and Finishing
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• v.22 no.1
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• pp.77-82
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• 2010

Highly conductive yarn was successfully obtained using electroless nickel plating method with palladium activation. In the presence of palladium seed on surface of fibers as a catalyst, continuos nickel layer produced on surface of fibers by reducing $Ni${2+}$ ion in the electroless plating bath to $Ni^0$. It was found that the Pd-activation using $SnCl_2$ and $PdCl_2$ to deposit palladium seeds on the surface of fibers plays a key role in the subsequent electroless plating of nickel. It also found that electroless nickel plating on the fibers can induce the nickel-plated $ELEX^{(R)}$ fibers to improve the electrical conductivity of the fibers. The thickness of nickel coating layer on the Pd-activated $ELEX^{(R)}$ fibers and specific conductivity of the fiber were increased through electroless plating time. The temperature of nickel plating bath was very effective to enhance the nickel deposition rate.

• Journal of Electrochemical Science and Technology
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• v.1 no.2
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• pp.117-120
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• 2010

Materials used as fuel cell electrode should be light, high conductive, high surface area for reaction, catalytic surface and uniformity of porous structure. Nickel is widely used in electrode materials because it itself has catalytic properties. When used as electrode materials, nickel of only a few im on the surface may be sufficient to conduct the catalytic role. To manufacture the nickel with porous structure, Electroless nickel plating on carbon fiber be conducted. Because electroless nickel plating is possible to do uniform coating on the surface of substrate with complex shape. Acidic bath and alkaline bathe were used in electroless nickel plating bath, and pH and temperature of bath were controlled. The rate of electroless plating in alkaline bath was faster than that in acidic bath. As increasing pH and temperature, the rate of electrolee plating was increased. The content of phosphorous in nickel deposit was higher in acidic bath than that in alkaline bath. As a result, the uniform nickel deposit on porous carbon fiber was conducted.

• Corrosion Science and Technology
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• v.23 no.1
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• pp.64-71
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• 2024

The objective of this study was to investigate corrosion and cavitation-erosion characteristics of the electroless nickel plating layer with heat treatment. The crystallization temperature of the electroless nickel plating layer was about 410 ℃. The phase transformation energy was confirmed to be 12.66 J/g. With increasing heat treatment temperature, the amorphous electroless nickel plating layer gradually changed to crystalline Ni and Ni₃P. At the same time, the crystal grain size was also increased. Additionally, when heat treatment was performed at a temperature above 400 ℃, NiO phase was observed due to oxidation phenomenon. As a result of the electrochemical polarization experiment, the corrosion resistance of the heat-treated electroless nickel plating layers was superior to that of the as-deposited plating layer. This was because crystal grains became larger and grain boundaries decreased during heat treatment. The cavitation-erosion resistance of heat-treated plating layers tended to be superior to that of as-deposited plating layers due to increased microhardness.

• Journal of the Korean institute of surface engineering
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• v.15 no.1
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• pp.1-10
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• 1982

Electroless plating is the continious formation of metallic coatings from metal ions by che-mical reduction without the use of electrical current. This is, however, more expansive than the conventional electroplating but is often used because of certain adventage. Here, general description of past research on electroless nickel plating, especially about the merits of each research was given. Part(Ⅰ) is for the conposition of solution, pretreatment and facilities of electroless nickel plating.

• Resources Recycling
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• v.21 no.2
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• pp.41-46
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• 2012

An investigation on the recovery of nickel from spent electroless plating solutions has been performed using the electrowinning method. For this aim, nickel in spent electroless plating solutions was separated as nickel hydroxide through the addition of caustic soda. Nickel hydroxide was completely dissolved with sulfuric acid and an electrolysis was performed for electrowinning of nickel from nickel solutions. As a result, it was found that more than 99% of nickel in spent electroless plating solutions could be precipitated as nickel hydroxide above pH 10 with the addition of caustic soda. As far as the current efficiency in electrowinning of nickel was concerned, it was decreased with increase in the current density.

• Korean Journal of Metals and Materials
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• v.48 no.1
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• pp.90-100
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• 2010

Micro-conductive patterns were microfabricated on an insulating substrate ($SiO_2$) surface by a selective electroless nickel plating process in order to investigate the formation of seed layers. To fabricate micro-conductive patterns, a thin layer of metal (Cu.Cr) was deposited in the desired micropattern using laser-induced forward transfer (LIFT). and above this layer, a second layer was plated by selective electroless plating. The LIFT process. which was carried out in multi-scan mode, was used to fabricate micro-conductive patterns via electroless nickel plating. This method helps to improve the deposition process for forming seed patterns on the insulating substrate surface and the electrical conductivity of the resulting patterns. This study analyzes the effect of seed pattern formation by LIFT and key parameters in electroless nickel plating during micro-conductive pattern fabrication. The effects of the process variables on the cross-sectional shape and surface quality of the deposited patterns are examined using field emission scanning electron microscopy (FE-SEM) and an optical microscope.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.625-628
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• 1999

Recently. high-density printed circuit boards(PCB) become indispensable with the minaturization of components. Nickel is deposited on the copper patterns and followed by the gold deposition for improving connection reliability between the printed circuit boards and electronic components. Conventionally electrodeposition has been applied to metalization of copper patterns. However metalization by this method is not applicable for the isolated fine and concentrated patterns. Therefore, metalization technology of the fine patterns by electroless plating is required in place of electrodeposition. The application of electroless nickel plating for interconnection with solder strongly relies on the solderability and the interactions between nickel and solder. Factors such as phosphorus content of the deposit additive and bath temperature may influence solderability of the electroless nickel deposit. So solderability of electroless nickel/ gold deposits was investigated with substrates plated changing the condition of nickel solution.

• Journal of the Korean Electrochemical Society
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• v.3 no.4
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• pp.196-199
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• 2000

Electroless plating is the desirable surface treatment method which is being widely used to all kinds of material such as requiring corrosion resistance, wear resistance and conductivity, especially plating of nonconductive material. Electroless nickel deposit has particular characteristics including non-magnetic property, amorphous structure, wear resistance, corrosion protection and thermal stability. In this study, electroless nickel plating was studied with an change in hardness and corrosion resistance of electroless nickel-phosphorus deposit depending on heat treatment. The highest hardness value was obtained by heat treatment at $500^{\circ}C$ Corrosion resistance of deposit, which had been heated at $300^{\circ}C$, was excellent when it was immersed in 1M $H_2SO_4$ solution for 60 hrs.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.270-274
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• 2001

With Increasing importance of electroless nickel plating technology in many fields such as electronic and automobile industries, the treatment of the spent baths is becoming a serious problem. These spent baths contain iron and zinc as impurities, organic acids as complexing reagents, and phosphonate ions as oxidized species of tile reducing reagent. as well as several grams per liter of nickel. The spent baths are currently treated by conventional precipitation method. but a mettled with no sludge generation is desired. This work aims at establishing a recycling process of nickel from tile spent baths using solvent extraction. Extraction behaviors of nickel. iron. and zinc in various 쇼pes of real spent baths are investigated as a function of pH using LIX841, di (2-ethylhexyl)phosphoric acid (D2EHPA), and PC88A as tile extractants. Nickel is extracted by LIX84I at the equilibrium pH of more than 6 with high efficiency. For the weakly acid baths. iron and zinc are extracted by D2EHPA or PC88A without adjusting the pH of the baths leaving nickel in the aqueous phase. Stripping of nickel from LIX84I with sulfuric acid is also investigated. It is shown that concentrated nickel sulfate solution (> 100 ㎏-Ni/㎥) is obtained. This solution can be reused in the electroless plating process. Based on these findings, flow sheets for recovering nickel from the spent baths are proposed.