• 한국표면공학회지
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• 제23권1호
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• pp.34-43
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• 1990

Al-Si piston alloys such as AlS10CuMg have been anodized to examine apossibility of forming a hard film aat relatively higher temperatures compard with those in conventional sulfuric acid processes. Three types of electrolytes have been employed in this study ; electrolyte A(15% H2SO4, $0^{\circ}C$), electrolyte B(12% H2SO4, 1% oxalic, $10^{\circ}C$), electrolyte C(tartaric acid 125g/L+oxalic 75g/L+aluminum sulfate 225g/L, $25^{\circ}C$). Hard anodisine process in electrolyte B at a current density of 1.54A/dm2 produced a harder film of VHN 396 at a relatibely low film forming voltage compared with those obtained in other electrolyte at equivalent current density. A liner relationship between hardness and abrasion resistance exists for Al-Si piston alloys. The hardness of anodized film decreasees with increasing silicon content in Al-Si alloys and also with bath temperature. The film hardeness of Na-modified alloy os higher than that of P-modified alloy due to its finer microstructre. The film on the silicon phase in Al-Si alloys is observed to be formed by lateral growth of oxide film nucleated at surroundings.

• 한국광학회지
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• 제20권4호
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• pp.236-240
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• 2009

LED 조명과 액정 후면 배광 장치와 같이 고방열, 고출력 광원이 요구되는 응용제품에 적합한 LED 광원 모듈을 제작하였다. 제안한 LED 광원 모듈은 기존 패키지 구조의 LED 광원과 다르게 LED 칩을 응용제품의 필요에 따른 배광 분포 제어와 광자재흡수를 개선하기 위해 반사컵 구조를 적용한 금속 기판의 표면에 LED 칩을 바로 실장하였다. 또한 기존 금속기판에 적용하던 알루미늄 산화막 절연층의 문제점을 개선하여 방열 특성을 향상시켰다. 나아가 방열 특성 개선으로 LED 칩에서 발생하던 열에 의해 발생하던 광효율 저하 문제를 개선하는 결과를 얻었다.

• 한국표면공학회지
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• 제17권3호
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• pp.78-86
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• 1984

Hard anodic oxide film was investigated formed on pure aluminium with various temperature (30$^{\circ}-60^{\circ}C$), current densities (1.5-3.0A/$dm^2$) and concentrations(3-15g/l) of oxalic acid in 0.5M malic acid bath. The resulting characteristic of the anodic oxide film obtained were summarized as follows in the view point of physical and mechanical properties in relation with the above process variables. 1. The film thickness increased with oxalic acid concentration and bath temperature, while the reversed phenomena were obtained at a high concentration of oxalic acid and high temperature due to the severe dissolution of the anodic oxide film. 2. The hardness and the abrasion resistance were improved by lowering the addition of oxalic acid and the bath temperature. This feature was directly dependent on the porosity formed on the anodic oxide film. 3. The maximum hardness of anodic oxide film showed Hv 579 in the temperature of 30$^{\circ}C$ with the current density, 2.5A/$dm^2$ in the 0.5M malic acid bath mixed with 5g/l oxalic acid.

• 한국전기전자재료학회논문지
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• 제26권10호
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• pp.766-770
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• 2013

This paper tried to develop a BLDC electric motor securing the 800 W-level watertight structure for driving the outboard motor. For this purpose, this paper developed a high-efficient controller-integrating BLDC electric motor system for underwater propulsion and designed and developed a triple watertight structure. Besides, this study developed a outboard motor integrating motor, propeller and controller based on the production of a controller for BLDC motor which can the speed control by selecting low-voltage, high-current power element. The characteristics of developed outboard motor were 24 V input voltage, over 800 W motor output, and max. 3,000 rpm motor, and 84.9% motor efficiency, and the developed outboard motor could secure the watertight structure in 5 m in water depth.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.273-278
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• 2003

Recently, high-performance hybrid composite materials have been used for various industrial fields because of their superior high strength, high stiffness and lower weight. In this study, manufactured hybrid composite materials are composed of two parts. One is hard-anodized Al5083-O alloy as a face material and the other is high strength aramid fiber ($Twaron^{(R)}$ CT709) laminates as a back-up material. Resistance to penetration is determined by protection ballistic limit($V_{50}$, a static velocity with 50% probability for complete penetration) test method. $V_{50}$ tests with $0^{\circ}$obliquity at room temperature were conducted with 5.56mm ball projectiles that were able to achieve near or complete penetration during high velocity impact tests.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1378-1381
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• 2003

Recently, high-performance composite materials have been used for various industrial fields because of their superior high strength, high stiffness and lower weight. In this study, manufactured fiber reinforced metal laminate materials are composed of two parts. One is hard-anodized A15083-O alloy as a face material and the other is high strength aramid fiber (Twaron CT709) and polyethylene fiber(Dyneema HB25) laminates as a back-up material. Resistance to penetration is determined by protection ballistic limit(V$\sub$50/, a static velocity with 50% probability for complete penetration) test method. V$\sub$50/ tests with 0$^{\circ}$ obliquity at room temperature were conducted with 5.56mm ball projectiles that were able to achieve near or complete penetration during high velocity impact tests.

• 전기화학회지
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• 제8권3호
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• pp.125-129
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• 2005

본 연구에서는 고순도 알루미늄 호일$(t=300{\mu}m)$양극산화 공정을 통해 AAO 나노템플레이트를 자체 제조하였고, 이렇게 제조된 형틀을 가지고 교류 나노전주법에 의해 경자성 합금인 CoP와 연자성 합금인 CoFe를 나노와이어로 제조하였다. 대표적인 Co계 자성합금인 CoP와 CoFe나노와이어는 각기 독특한 자기적 성질을 나타내었다. 경자성 CoP 합금 나노와이어의 경우 교류 인가전압에 따라 hcp와 fcc가 혼재된 구조가 형성되어 자기적 특성에 영향을 미쳤다. 또한 높은 포화자화 값을 갖는 CoFe연자성 합금 나노와이어는 박막 도금 시와는 달리 이상합금도금현상이 거의 나타나지 않았으며 $Co_{30}Fe_{70}$에서 가장 좋은 238emu/g의 포화자화 값을 나타내었다.

• 한국군사과학기술학회지
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• 제27권4호
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• pp.457-465
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• 2024

The Remote Control Munition System is a anti-personnel munitions system to replace land mines that are hard to retrieve and can inflict damage on friendly forces and civilians. As operating environments and methods change, quality improvement is necessary to ensure appropriate durability. Therefore, corrosion resistance evaluation was performed according to the surface treatment of ALDC12, the main assembly material. We conduct the potentiodynamic polarization, cyclic corrosion test to perform analysis on corrosion behavior. Additionally, we try to observe the pitting on the surface through SEM analysis. In conclusion, among the three surface treatments, Anodizing surface treatment is judged to be the most suitable for corrosion durability in a field environment.