• Macromolecular Research
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• v.12 no.5
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• pp.431-436
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• 2004

Cross-linked network solid polymer electrolytes were prepared by means of in situ hydrosilylation between poly[hydromethylslioxane-g-oligo(ethylene oxide)] and diallyl or triallyl group-containing poly(ethylene glycols). The conductivities of the resulting polymer electrolytes were greatly enhanced upon the addition of poly(ethylene glycol) dimethyl ether (PEGDME) as an ion-conducting plasticizer. Conductivities of the cross-linked polymer electrolytes were more dependent on the molecular weight of PEGDME than on the cross-linkers. The maximum conductivity was found to be 5.6${\times}$10$\^$-4/ S/cm at 30$^{\circ}C$ for the sample containing 75 wt% of PEGDME (M$\_$n/ =400). These electrolytes exhibited electrochemical stability up to 4.5 V against the lithium reference electrode. We observed reversible electrochemical plating/stripping of lithium on the nickel electrode.

• Journal of Surface Science and Engineering
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• v.48 no.3
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• pp.100-104
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• 2015

The nickel alloys gets a great deal of attention due to their good mechanical, chemical and magnetic properties. Especially Ni-P alloy systems are very attractive due to their good corrosion resistance and the wear resistance in important technological applications. In this study, the effects of phosphorus acid concentration in plating solution on composition of Ni-P alloy coatings were studied. The Ni-P electrodeposits of the various P contents were investigated in order to understand effect of the composition on mechanical properties of Ni-P electrodeposits. The mechanical properties of electrodeposits increased as the P content in electrodeposits increase. The results of mechanical properties were explained by grain size and P solid solution effect. The effects of heat treatment on mechanical properties of Ni-P alloy coatings were also studied.

• 연구논문집
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• s.22
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• pp.151-160
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• 1992

The wear resistance of electroless Ni-P-X(X A1203, Diamond) composite coating layers was studied by Taber abrasion test technique. The wear resistance of composite coating layers was particularly relied upon the codeposited content, particle size and distribution of particles, and heat treatment of coating layers, as well as the electroless nickel plating bath employed. In this study, we lay emphasis on the wear resistance of electroless composite coating layers containing A1203 particles(1.2~Im, 6.7hIm, 11.5lIm, 20l1m) or diamond particles (1.5jim, 5gm). From the result of composite coating A1203 and diamond particles, the wear resistance of composite coating layers is as follows.

• Proceedings of the KAIS Fall Conference
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• 2004.06a
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• pp.65-68
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• 2004

순간금형가열방법(MmSH injection process)과 일반적인 방법으로 사출된 ABS 위에 전자파를 차폐하기 위한 무전해 Ni 과 Ag도금을 하였다. 무전해 Ni의 경우, 알칼리성 도금욕일수록 도금속도가 증가하였고 순간금형가열방법으로 사출된 ABS가 일반적인 방법으로 사출된 ABS 보다 밀착력, 광택. 전자파 차폐효율이 다소 높은 값을 가졌으며 pH 8에서 5B의 밀착력, 509의 광택도와 76dB의 전자파 차폐효과를 나타냈다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.5
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• pp.433-437
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• 2004

The MmSH is a process of injecting ABS to produce innovated physical properties compared to the conventional injection process. Physical properties such as thickness and adhesion strength of Ni plate electrolessly coated on a conventional and a MmSH injected ABS have been studied in the pH range 4~8. Thickness of the plate on the MmSH and the conventionally injected ABS appeared to be directly proportional to pH. The ABS processed by the conventional injection showed adhesion strength corresponded to ASTM 4B above pH 5. On the other hand, the ABS processed by the MmSH injection showed a superior adhesion strength corresponded to ASTM 5B above pH 6. It was calculated the shielding effectiveness of above 50 dB in all conditions.

• Journal of Surface Science and Engineering
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• v.33 no.5
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• pp.356-364
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• 2000

Factors that affect the hardness of the zinc electrodeposits in the sulfate electrolyte were investigated. The hardness of zinc deposit was enhanced by increasing the concentration of impurities such as iron and nickel in the bath that changed the crystallographic orientation of the zinc deposit from the strong basal plane to the random orientation. The increase of the concentration of sodium sulfate and current density in iron contained bath improved the hardness of zinc deposit because those were easily codeposited in zinc layer. However the increase of the concentration of sodium sulfate up to 80g/$\ell$ in the bath darkened the surface of zinc electrodeposits due to change of morphology by the codeposition of iron.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.318-318
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• 2012

최근 고급스러운 표면을 가지는 제품의 수요가 증가함에 따라 pore를 통하여 rough한 표면을 구현하고 광택을 줄인 사틴 도금이 각광받고 있다. 사틴 효과를 구현하기 위하여 도금 용액에 첨가되는 첨가제의 종류 중 에멀젼 타입의 사틴 첨가제는 시간이 경과함에 따라 첨가제 입자들의 뭉침 현상이 발생하기 때문에 건욕 후 2시간이 경과하면 사틴 효과가 감소하게 되고 연속 공정이 불가능하다. 이에 본 연구에서는 크기가 증가한 첨가제 입자들만을 제거한 후 첨가제를 소량씩 재첨가하여 사틴 니켈의 연속 공정이 가능하도록 필터링 및 첨가제 보충이 가능한 필터링 시스템을 도입하였다. 필터링 시스템에 의하여 2시간 경과 후 발생되는 뭉쳐진 첨가제가 선택적으로 제거 되어 pore의 크기를 제어할 수 있었으며 제거된 첨가제는 재첨가로 인해 보충되어 pore의 크기와 개수도 유지 할 수 있었다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2002.05a
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• pp.37-37
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• 2002

Diamoncl/Mo/Ni multi-layers on SKH-51 steel substrate was prepared to improve the abrasive wear resistance of a tool and die by a commercial chemical vapor deposition unit and electro-plating. The diamond after 7 hour deposition had cuba-octahedral structure with 2~5$\mu\textrm{m}$ grains. The existence of non-ferrous metals such as chromium, nickel and molybdenum between diamond and SKH-51 substrate results in forming higher quality of diamond layer by retarding carbon diffusion in the diamond layer during deposition, and also improving hardness and wear resistance. Surface cracks on the film was sometimes observed by the difference of by the thermal expansion coefficients between the steel substrate and the deposited layers during cooling.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.3
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• pp.69-75
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• 2016

This study investigated the effect of heat treatment conditions not only on the Cr surface crack propagation behaviors but also on the Ni/Cr interfacial reaction characteristics in electroless Ni/electroplated Cr double coating layers on Cu substrate. Clear band layer of Ni-Cr solid solutions were developed at Ni/Cr interface after heat treatment at $750^{\circ}C$ for 6 h. Channeling cracks formed in Cr layer after 1 step heat treatment, that is, heat treatment after Ni/Cr plating, while little channeling cracks formed after 2 step heat treatment, that is, same heat treatments after Ni and Cr plating, respectively, due to residual stress relaxation due to crystallization of Ni layer before Cr plating.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.7
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• pp.46-52
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• 2006

The effects of surface treatment on the hydrogen storage properties of a $Mg_2Ni$ alloy particle were investigated by the microvoltammetric technique, in which a carbon-filament microelectrode was manipulated to make electrical contact with the particle in a KOH aqueous solution. It was found that the hydrogen storage properties of $Mg_2Ni$ at room temperature were improved by the surface treatment with a nickel plating solution. The sodium salts(sodium phosphate and sodium dihydrogen citrate) contained in the nickel plating solution made the alloy form an amorphous-like state, resulting in an improved hydrogen charge/discharge capacity at room temperature as high as about 150[mAh/g] from the original value of 17[mAh/g]. Potential-step experiment was carried out to determine the apparent chemical diffusion coefficient of hydrogen atom($D_{app}$) in the alloy. Since the alloy particle we used here was a dense, conductive sphere, the spherical diffusion model was employed for data analysis. $D_{app}$ was found to vary the order between $10^{-8}{\sim}10^{-9}[cm^2/s]$ over the course of hydrogenation and dehydrogenation process.