• Journal of Welding and Joining
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• 제31권6호
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• pp.58-64
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• 2013

Several joining methods involving resistance welding, laser welding, ultrasonic welding and mechanical joining are currently applied in manufacturing lithium-ion batteries. Cu and Al alloys are used for tab and bus bar materials, and laser welding characteristics for these alloys were investigated with similar and dissimilar material combinations in this study. The base materials used were Al 1050 and oxygen-free Cu 1020P alloys, and a disk laser was used with a continuous wave mode. In bead-on-plate welding of both alloys, the joint strength was higher than the strength of O tempered base material. In overlap welding, the effect of welding parameters on the tensile shear strength and bead shape was evaluated. Tensile shear strength of overlap welded joint was affected by interfacial bead width and weld defect formation. The tensile-shear specimen was fractured at the heat affected zone by selecting proper laser welding parameters.

• Bulletin of the Korean Chemical Society
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• 제29권1호
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• pp.245-248
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• 2008

• 한국재료학회:학술대회논문집
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• 한국재료학회 2005년도 춘계학술발표대회 및 제8회 신소재 심포지엄 논문개요집
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• pp.207-207
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• 2005

• 한국표면공학회지
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• 제45권4호
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• pp.151-154
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• 2012

A hydrophobic surface has been fabricated on aluminum by two-step surface treatment processes consisting of structure modification and surface coating. Nature inspired micro nano scale structures were artificially created on the aluminum surface by a blasting and Ar ion beam etching. And a hydrophobic thin film was coated by a trimethylsilane ($(CH_3)_3SiH$) plasma deposition to minimize the surface energy of the micro nano structure surface. The contact angle of micro nano structured aluminum surface with the trimethylsilane coating was $123^{\circ}$ (surface energy: 9.05 $mJ/m^2$), but the contact angle of only trimethylsilane coated sample without the micro nano surface structure was $92^{\circ}$ (surface energy: 99.15 $mJ/m^2$). In the hydrophobic treatment of aluminum surface, a trimethylsilane coated sample having the micro nano structure was more effective than only trimethylsilane coated sample without the micro nano structure.

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1139-1143
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• 2014

The adsorption behavior of the sulphate ($SO{_4}^{2-}$) on the external surface of (5,0), (8,0), and (10,0) zigzag AlNNTs was studied by using density functional calculations. Adsorption energies in the nanotubes are about -8.59, -8.04, -8.60 eV with a charge transfer of 0.59, 0.48, 0.56|e| from the sulphate ion to the nanotubes, respectively. The adsorption energies indicated that sulphate ion can be absorbed strongly on the nanotubes. Therefore, these nanotubes can be used for adsorption of sulphate ion from the environmental systems. It was found that diameter of the AlNNTs has slight role in the adsorption of sulphate ion. The electronic properties of the nanotubes showed notable changes upon the adsorption process.

• 한국진공학회지
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• 제12권S1호
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• pp.74-78
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• 2003

In this paper, we studied, by numerical calculation, a system, which was composed of metal-film and metal-substrate irradiated by IPIB with beam ion energy 250 keV, current density 10 to 250 A/$\textrm{cm}^2$. While the IPIB irradiation was going on, an induced effect named mixing occurred. In this case, metal-film and part of metal-substrate melted and mixed. The mixing state was kept as it was in melting phase due to the fast cooling rate. Our works were simulating the heating and cooling process via our STEIPIB program and tried to find proper parameters for a specific film-substrate system, 500 nmtitanium film coated on aluminum, to get best mixing results. The parameters calculated for such Ti-Al system were compared with the experimental results and were in good accordance to the experimental results.

• 공업화학
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• 제34권4호
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• pp.450-454
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• 2023

플럭스 코어 아크 용접(flux cored arc welding, FCAW)에서 플럭스(flux)로 사용되는 합금 분말 내의 염소이온은 용접 금속의 비드 표면에 기공을 유발하여 불량을 유발하거나, 합금 분말에 잔류한 염소가 금속의 부식을 유발할 수 있다. 합금 분말의 염소이온 정량은 주로 연소-이온크로마토그래피법이 사용되나, 장비가 고가이며 고도의 전문성이 요구되는 한계가 있다. 따라서, 본 연구에서는 합금 분말의 염소이온 정량으로 주로 쓰이는 방법인 연소-이온크로마토그래피 법과 X-선 형광분석법, 그리고 전위차 적정법을 비교하여 현장에서 적용하기 쉽고 정확한 정량법을 찾고자 한다. 염소이온 정량의 대상으로는 플럭스로 가장 흔히 사용되는 마그네슘-알루미늄 합금 분말을 대상으로 한다. 본 연구의 결과를 통해, 전위차 적정법을 현장에서 합금 분말의 염소이온 정량에 적용할 수 있다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.252-256
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• 2001

The rapid development of communication equipment and information processing technology has led to a constant improvement in cordless communication. Lithium ion batteries used in cellular phones and laptop computers, in particular, have been in the forefront of the above revolution. These batteries use high value added raw materials and have a high and stable energy output and are increasingly coming into common use. The development of the material for the negative terminal has led to an improvement in the quality and efficiency of the batteries, whereas a reduction in the cost of the battery by researching new materials for the positive anode has become a research theme by itself. These long life batteries, it is being increasingly realized, can have value added to them by recycling. Research is increasingly being done on recycling the aluminum case and the load casing for the negative diode. This paper aims to introduce the current situation of recycling of lithium ion batteries. 1. Introduction 2. Various types of batteries and the situation of their recycling and the facts regarding recycling. 3. Example of cobalt recycling from waste Lithium ion secondary cell. 3-1) Flow Chart of Lithium ion battery recycling 3-2) Materials that make a lithium ion secondary cell. 3-3) Coarse grinding of Lithium ion secondary cell, and stabilization of current discharge 3-4) Burning 3-5) Grinding 3-6) Magnetic Separation 3-7) Dry sieving 3-8) Dry Classifying 3-9) Content Ratio of recycled cobalt parts 3-10) Summary of the Line used for the recovery of Cobalt from waste Lithium ion battery. 4. Conclusion.

• Corrosion Science and Technology
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• 제14권2호
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• pp.85-92
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• 2015

An on-line corrosion rate measurement system was developed using a personal computer, a data acquisition board and program, and a 2-electrode corrosion probe. Reliability of the developed system was confirmed with through comparison test. With this system, the effect of sodium nitrite ($NaNO_2$) as a corrosion inhibitor were studied on iron and aluminum brass that were immersed in sodium chloride (NaCl) solution. Corrosion rate was measured based on the linear polarization resistance method. The corrosion rates of aluminum brass and iron in 1% NaCl solutions were measured to be 0.290 mm per year (mmpy) and 0.2134 mmpy, respectively. With the addition of 200 ppm of $NO{_2}^-$, the corrosion rates decreased to 0.0470 mmpy and 0.0254 mmpy. The addition of $NO{_2}^-$ caused a decrease in corrosion rates of both aluminum brass and iron, yet the $NO{_2}^-$ acted as a more effective corrosion inhibitor for iron. than aluminum brass.

• 소성∙가공
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• 제13권3호
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• pp.285-289
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• 2004

Micro tensile test specimens of thin film single crystal silicon for the most useful structural materials in MEMS (Micro Electro Mechanical System) devices were fabricated using SOI (Silicon-on-Insulator) wafers and MEMS processes. Dimensions of micro tensile test specimens were thickness of $7\mu\textrm{m}$, width of 50~$350\mu\textrm{m}$, and length of 2mm. Top and bottom silicon were etched using by deep RIE (Reactive Ion Etching). Thin film aluminum markers on testing region of specimens with width of $5\mu\textrm{m}$, lengths of 30~$180\mu\textrm{m}$ and thickness of 200 nm for measuring tensile strain were fabricated by aluminum wet etching method. Fabricated side wall angles of aluminum marker were about $45^{\circ}~50^{\circ}$. He-Ne laser with wavelength of 633nm was used for checking fringed patterns.