• Journal of the Korean institute of surface engineering
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• v.9 no.3
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• pp.1-4
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• 1976

In order to get high wear-resistant gold alloy plating on electronic parts, on attempt has been made, in which Cu, Ni, and Zn EDTA salts were added in gold palting solution. The results obtained on the wear resistance are as follows: 1. The addition of 0.5g/ι or over Cu in plating solution, showed 1.5 times more wear resistance than in case of no addition. 2. The addition of 1.5g/ι or over Ni, showed 3.5 times more wear-resistance . 3. The addition of 1.5g/ι and 4.0g/ι Zn , showed 3.5 times and 6.8 times more wear resistance , respectively. 4. The addition of 1.5g/ι Ni and 1.0g/ι Zn simultaneously , showed about 10 times more wear resistance than in case of no addition.

• Bulletin of the Korean Chemical Society
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• v.28 no.8
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• pp.1285-1288
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• 2007

Au was electrolessly deposited on polycarbonate (PC) membranes (0.1 μm pores) at the air/water interface. It was found that the Au nanotube dimension can be controlled by adjusting the plating temperature and the solution composition. Interfacial deposition of Au at relatively low temperatures (4℃) produced long nanotubes, which run through the whole membrane thickness with small openings. Increase of plating temperatures resulted in the decrease of nanotube lengths and Au film thicknesses. It was also disclosed that the inside-diameter of Au nanotubes can be controlled with negligible variations in length by changing the composition of a plating solution.

• Journal of the Korean institute of surface engineering
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• v.37 no.6
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• pp.335-343
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• 2004

Bath stabilizers in the electroless nickel(EN) plating solution are known to prevent sudden bath decomposition and extend its lifetime. Further, every stabilizer has a different role and function in EN solution and it influences the surface structure. In this study, the effects of various stabilizers on the deposition rate, surface morphology, deposition content of phosphor and hardness were investigated.

• Bulletin of the Korean Chemical Society
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• v.16 no.3
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• pp.221-226
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• 1995

A method for determining nitrate in post treatment chromium plating solutions with PVC-based nitrate-selective electrodes is described. PVC-based nitrate-selective membranes which contain TDMANO3 ion-exchanger in PVC/NPOE, PVC/DOA or PVC/DBP matrices, and a commercially available Corning electrode (No. 476134) have been compared in respect of their detection limits, response slopes, selectivities at various pHs, and dynamic response to the hydrochromate ion in basic condition. The PVC/DBP/TDMANO3 membrane electrode was chosen as the ISE detector for the determination of nitrate in the presence of hydrochromate interference. The amount of nitrate in real post treatment chromium plating solution could be determined successfully with this electrode in both static and flow-injection measurements when the sample was properly diluted with an alkaline buffer.

• Corrosion Science and Technology
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• v.4 no.6
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• pp.222-225
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• 2005

The adhesion strength of metal plating on PC was studied. In this study, surface was treated by chemical agents or DBD(dielectric barrier discharge) plasma to imporve the adhesion. The surface roughness, contact angle, gloss of plating and adhesive strength were measured. Adhesion strengths of Ni plating on prepared PC by NaOH and KOH solution were $12.3kgf/cm^2$ and $7.5kgf/cm^2$, respectively. The highest adhesion strength was obtained in the plasma treated one, $27.8kgf/cm^2$.

• Clean Technology
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• v.11 no.3
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• pp.153-164
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• 2005

This study found a reliable evaluation for four kinds of pb-Free plating solutions and it's layers, through pure Sn, SnAg, SnBi and SnCu. These four kind of solutions are widely used to pb-Free plating. Hull-cell, Harring-blum, coverage, throwing power, current efficiency, stability, life-time, composition, hardness, roughness, abrasion, scratch, solderability, corrosion, contact angle, morphology, SIR(Surface insulation resistance) and Whisker test were experimented. Also, Using ICP, XRF, FE-SEM, EDS, temperature/humidity chamber, solderability tester, hardness tester, roughness tester, abrasion tester, salt spray tester, contact angle tester, SIR tester, and microscope. In this paper could be shown the systematic and various analysis for reliability about four kinds of pb-Free plating solutions, processes and it's deposit surface.

• Journal of the Korean institute of surface engineering
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• v.23 no.4
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• pp.208-217
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• 1990

Electroless Ni-Cu-P plating was performed was performed to investigate for plating and changes in microhardness and corrosion rate of of electroless deposits depending on heat treatment. The activation energy for $75~85^{\circ}C$ were calculated to be 66.7KJ/mole. Plating rate increased to 34% with addition of 200ppm of NaF and 0.8ppm of thiourea to the bath. The highest hardness value was obtained by heat treatment deposits layer at$ 400^{\circ}C$, 1 hour. The increase in hardness of deposits by heating was confirmed to be associated with crystallization of the amorphous deposits. Corrosion resistance of deposir layer, which had been heated up to $300^{\circ}C$, was found to be exellent when immersed in 1N-H2SO4 solution, Change of the corrosion resistance seems to have some important bearing on content of amorpous, Ni3P and Cu3P.

• Journal of the Korean institute of surface engineering
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• v.30 no.2
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• pp.104-110
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• 1997

Conventional hexavlent chromium electroplating baths deposit the matal at low cathode efficiency and have poor covering and throwing power. The processs also generate hazardous wastes. To overcome many of the disadvantages of hexavalent chromium plating the use of trivalent chromium has advocted. After Yoshida, who first studied trivalent chromium plating, using ammonium sulfate and urea, there are numerous report describing the trivalent chromium electropating process using complexing agents. This study investigaten trivalent chromium plating electrolyte solutious containing formate as a complexing agent and ammouim chloride for conducting agent. The effects of composition and operating conditions on deposits and current efficiencies were investigated in trivalent chromium plating baths by analyzing the relationship pulse conditions and surface morphology The surface morphology of the deposits was observed by SEM. pulse electrolysis has been effective on obtaining a smooth with high current efficiency comparing with D.C. electrolysis in trivalent chromium solution.

• Korean Journal of Materials Research
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• v.5 no.7
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• pp.794-801
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• 1995

To connect the driver IC and Al coated glass, a method has been developed to plate electrolessly Ni on Al/PR system. It Is necessary to pretreat Al to remove oxide film before plating. In order to find pretreatment process which does not damage photoresist or glass, alkaline and fluoride zincate process have been investigated. Because photoresist and aluminum thin film can easily dissolve in alkaline solution, it is considered that the fluoride zincate process was a suitable one. After immersion in the zincate solution containing 1.5 g/$\ell$ ammonium bifluoride and 100 g/$\ell$ zinc sulfate, electroless nickel plating could be performed. The additive in the zincate solution and thiourea in the plating solution increased smoothness of the plated surface. Acld dip could improve the uniformit of the surface.

• Corrosion Science and Technology
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• v.23 no.3
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• pp.215-220
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• 2024

Recently, the demand for Zn-Ni electrogalvanized steel sheets for home appliances and automobiles is increasing. Products should have a thick plating (30 to 40 g/m²) on both side with a thin thickness (≤ 0.8 mm) and the highest surface quality. By a high current density operation, current is concentrated in the edge part of the steel sheet, resulting in large surface dent defects due to dendritic plating. This can lead to a low productivity due to low line speed operation. To solve this problem, this study aimed to identify factors influencing dendritic plating. A cylindrical electroplating device was manufactured. Effects of cut edge shape and thickness of steel plate, current density, temperature, flow rate, electrolyte concentration, and pH on dendrite generation of Zn-Ni electroplating were examined. To investigate effect of edge shape of the steel sheet, the steel sheet was manufactured using three processing methods: shearing, polishing after shearing, and laser. Relative effects thickness and cut edge processing methods of the steel plate, current density, temperature, flow rate, electrolyte concentration, and pH of plating solution on dendrite plating were investigated. To prevent dendrite plating, an edge mask was manufactured and its application effect was investigated.