• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2008년도 춘계학술대회 논문집
• /
• pp.447-448
• /
• 2008

• Design & Manufacturing
• /
• 제2권5호
• /
• pp.5-10
• /
• 2008

Recently, ultra precision and light-weight micro products are needed in various industries. Injection molding products with metal insert material is often satisfied with light-weight and precision simultaneously. The researches on macro-size insert deformation have been performed but, a research on micro-size insert is meager. In this paper, the injection molding product with $300{\mu}m$ thin foil insert is designed and insert injection molding process is performed. Finally, the deformation of thin foil insert is analyzed according to insert feature and gate length.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2005년도 추계학술대회 논문집
• /
• pp.295-298
• /
• 2005

This paper is concerned with the precision material property measurement of a micro metal thin foil that is used in MEMS technology. Since these MEMS components require great precision and accuracy, evaluation of reliability such as the lift cycle endurance test, impact test, and residual stress test is necessary for these components. However, in practice, real reliability tests are not easy to perform due to consideration of various factors. Rather than actual testing, it would be much easier to evaluate the reliability of components by the analytical approach. Although the analytical method is utilized by software tools, it is obviously necessary to acquire fundamental properties of materials through real test methods. In this paper, the oriented mechanical properties of aluminum thin foil are measured by nano scale material property measurement system.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
• /
• pp.1455-1458
• /
• 2008

Amorphous silicon (a-Si:H) thin-film transistors (TFTs) are fabricated on flexible organic polymer foil substrates. As-fabricated performance, electrical bias-stability at elevated temperatures, electrical response under mechanical flexing, and prolonged mechanical stability of the TFTs are studied. TFTs made on plastic at ultra low process temperatures of $150^{\circ}C$ show initial electrical performance like TFTs made on glass but large gate-bias stress instability. An abnormal saturation of the instability against operation temperature is observed.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
• /
• pp.263-267
• /
• 2002

We are standing at the beginning of the industrialization of flexible thin-film transistor backplanes. An important group of candidates is based on silicon thin films made on metal or plastic foils. The main features of amorphous, nanocrystalline and microcrystalline silicon films for TFTs are summarized, and their compatibility with foil substrate materials is discussed.

• 한국연소학회:학술대회논문집
• /
• 한국연소학회 2007년도 제34회 KOSCO SYMPOSIUM 논문집
• /
• pp.27-30
• /
• 2007

We have been setting up experiments on propagation of shock waves generated by the pulsed laser ablation. One side of a thin metal foil is subjected to laser ablation as a shock wave is generated from a localized spot of high intensity energy source. The resulting reactive shock wave, which penetrates through the foil is reflected by an acoustic impedance which causes the metal foil to high-strain rate deform. This short time physics is captured on an ICCD camera. The focus of our research is generating reactive shock wave and high strain rate deforming of thin metal foil for accelerating micro-particles to a very high speed on the orders of several thousand meter per second. Somce innovative applications of this device will be discussed.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2004년도 추계학술대회논문집
• /
• pp.188-191
• /
• 2004

Electroforming is a process that employs technology similar to that used for electroplating but which is used for manufacturing metallic articles, rather than as a means of producing surface coatings. Electroforming provides a cost-effective means of producing alloys and fully dense nanocrystalline metals as foils, sheets and complex shapes. It was able to make Fe-Ni foil with $5{\mu}m$ thickness by electroforming. Electroformed Fe-Ni alloy was nanocrystalline and the yield strength was in the range $2000{\sim}2800\;MPa$. The magnetic permeability at high frequency of electroformed Fe-Ni foil was higher than that of thicker foils.

• 대한방사선기술학회지:방사선기술과학
• /
• 제2권1호
• /
• pp.95-99
• /
• 1979

When the ${\gamma}-ray$ of average energy 375KeV emitted by Ir-192 is exposed to each film through lead foil with various thickness, the film sensitivity will be different according to the thickness of lead foil and film type. The results on the study, different density and sensitive ratio appeared depending on exposed time and film type, but was made on the following common points. 1. The effect of film sensitivity by the front lead foil showed rapid increase up to the thickness of more or less 0.03mm, and the thicker lead foil was decreased more in the thickness of about $0.05{\sim}0.09mm$. 2. The effect of film sensitivity by the back lead foil was increased up to around of $0.03{\sim}0.08mm$ thickness, the maximum sensitivity was obtained in the thickness of more than $0.03{\sim}0.08mm$ without any change in the above effect. 3. The sensitivity of front lead foil was higher than that of back lead foil in thin lead foil with about 0.127mm thickness, but the sensitivity of back lead foil was higher than that of front lead foil when thickness became thicker.

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2007년도 제28회 춘계학술대회논문집
• /
• pp.353-357
• /
• 2007

본 연구의 목표는 고 에너지원이 고 출력 펄스 레이저를 이용하여 금속 표면에서 발생하는 충격파를 분석하고 이를 다른 분야에 적용하는 것이다. 금속 표면 일정 단면에 펄스 레이저를 조사시키면 충격파가 발생하며 이 충격파는 음향 임피던스에 의해 레이저가 조사된 반대 방향으로 극 초음속(4000m/s 이상)으로 매우 짧은 시간동안 진행하며 다른 표면에서도 고 에너지에 의해 충격파가 발생한다. 이와 함께 얇은 금속은 순간 탄성변형을 일으킨다. 짧은 시간에 발생하는 모든 현상은 ICCD카메라를 통해 확인 할 수 있다. 이 실험의 목적은 고 에너지에 의해 발생한 충격파를 이용하여 미립자를 매우 빠른 속도로 가속하는데 있다.

• Tribology and Lubricants
• /
• 제22권5호
• /
• pp.252-259
• /
• 2006

Air foil bearing supports the rotating journal using hydrodynamic force generated at thin air film. The bearing performances, stiffness, damping coefficient and load capacity, depend on the rotating speed and the performance of the elastic foundation, bump foil. The main focus of this study is to decide the dynamic performance of corrugated bump foil, structural stiffness and Coulomb damping caused by friction between bump foil and top foil/bump foil and housing. Structural stiffness is determined by the bump shape (bump height, pitch and bump thickness), dry-friction, and interacting force filed up to fixed end. So, the change of the characteristics was considered as the parameters change. The air foil bearing specification for analysis follows the general size; diameter 38.1 mm and length 38.1 mm (L/D=1.0). The results show that the stiffness at the fixed end is more than the stiffness at the free end, Coulomb damping is more at the fixed end due to the small displacement, and two dynamic characteristics are dependent on each other.