• Title/Summary/Keyword: nano-glass

Search Result 503, Processing Time 0.032 seconds

Fabrication of Conductive Pastes for Induction Cookware with the Variation of the Contents of Silver Powder and Glass Frit (인덕션 조리용기용 도전성 Paste의 Silver 및 Glass Frit 함량 변화에 따른 미세구조 및 전기적 특성 고찰)

  • Gu, Hyun Ho;Kim, Bong Ho;Yoon, Young Joon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.29 no.11
    • /
    • pp.690-695
    • /
    • 2016
  • Induction cooktop has a great attention due to its safety, quick heating and cleanness compared to gas oven. However, the materials for induction cookware is limited to steel or stainless-steel which has the magnetic property. Recently, it has been tried to apply various porcelain to induction cookware after printing the silver layer on the bottom of cookware plates and co-firing at high temperature. Glass frits are added in the silver paste to improve an adhesion force between porcelain materials containers and transferred silver layer. The hybrid silver pastes for induction cookware requires the proper electrical resistance and the thermal conductivity with base plates. After sintering process at $800^{\circ}C$, a part of melted glass migrated to the porcelain and the rest of the glass frit was exposed to the surface. It was confirmed that most of the glass frit formed an adhesion layer between the porcelain and transferred silver layer that enhances the adhesion force.

Fabrication of a Bottom Electrode for a Nano-scale Beam Resonator Using Backside Exposure with a Self-aligned Metal Mask

  • Lee, Yong-Seok;Jang, Yun-Ho;Bang, Yong-Seung;Kim, Jung-Mu;Kim, Jong-Man;Kim, Yong-Kweon
    • Journal of Electrical Engineering and Technology
    • /
    • v.4 no.4
    • /
    • pp.546-551
    • /
    • 2009
  • In this paper, we describe a self-aligned fabrication method for a nano-patterned bottom electrode using flood exposure from the backside. Misalignments between layers could cause the final devices to fail after the fabrication of the nano-scale bottom electrodes. A self-alignment was exploited to embed the bottom electrode inside the glass substrate. Aluminum patterns act as a dry etching mask to fabricate glass trenches as well as a self-aligned photomask during the flood exposure from the backside. The patterned photoresist (PR) has a negative sidewall slope using the flood exposure. The sidewall slopes of the glass trench and the patterned PR were $54.00^{\circ}$ and $63.47^{\circ}$, respectively. The negative sidewall enables an embedment of a gold layer inside $0.7{\mu}m$ wide glass trenches. Gold residues on the trench edges were removed by the additional flood exposure with wet etching. The sidewall slopes of the patterned PR are related to the slopes of the glass trenches. Nano-scale bottom electrodes inside the glass trenches will be used in beam resonators operating at high resonant frequencies.

Micromachining of Cr Thin Film and Glass Using an Ultrashort Pulsed Laser

  • Choi, Ji-Yeon;Kim, Jae-Gu;Shin, Bo-Sung;Whang, Kyung-Hyun
    • Journal of the Optical Society of Korea
    • /
    • v.7 no.3
    • /
    • pp.160-164
    • /
    • 2003
  • Materials processing by ultrashort pulsed laser is actively being applied to micromachining technology due to its advantages with regard to non-thermal machining. In this study, materials processing with ultrashort pulses was studied by using the high repetition rate of a 800 nm Ti:sapphire regenerative amplifier. This revealed that the highly precise micromachining of metallic thin film and bulk glass with a minimal heat affected zone (HAZ) could be obtained by using near damage threshold energy. Grooves with diffraction limited sub-micrometer width were obtained with widths of 620 nm on Cr thin film and 800 nm on a soda-lime glass substrate. The machined patterns were investigated through SEM images. We also phenomenologically examined the influence of variations of parameters and proposed the optimal process conditions for microfabrication.

Maskless Nano-fabrication by using both Nanoscratch and HF Wet Etching Technique (나노스크래치와 HF 에칭기술을 병용한 Pyrex 7740의 마스크리스 나노 가공)

  • 윤성원;이정우;강충길
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2003.06a
    • /
    • pp.628-631
    • /
    • 2003
  • This study describes a new mastless nano-fabrication technique of Pyrex 7740 glass using the combination of nanomachining by nano-indenter XP and HF wet etching. First, the surface of a Pyrex 7740 glass specimen was machined by using the nano-machining system, which utilizes the mechanism of the nano-indenter XP. Next, the specimen was etched by HF solution. After the etching process, the convex structure or deeper hole is made because of masking or promotion effect of the affected layer generated by nano-machining. On the basis of this interesting fact. some sample structures were fabricated.

  • PDF

A Making of Aesthetic Dental restorations with Nano Hybrid Ceramic material by CAD/CAM System (치과 CAD/CAM용 Nano Hybrid Ceranic 소재를 이용한 심미 치과보철물의 제작)

  • Choi, Beom-jin
    • Journal of the Korean Academy of Esthetic Dentistry
    • /
    • v.25 no.2
    • /
    • pp.98-108
    • /
    • 2016
  • In recent days, perhaps the biggest driver in new material development is the desire to improve restorations esthetics compared to the traditional metal substructure based ceramics or all-ceramic restorations. Each material type performs differently regarding strength, toughness, effectiveness of machining and the final preparation of the material prior to placement. For example, glass ceramics are typically weaker materials which limits its use to single-unit restorations. On the other hand, zirconia has a high fracture toughness which enables multi-unit restorations. This material requires a long time sintering procedure which excludes its use for fast chair side production. Hybrid ceramic material developed for CAD/CAM system is contained improved nano ceramic elements. This new material, called a Resin Nano Hybrid Ceramic is unique in durability of function and aesthetic base compositions. The new nano-hybrid ceramic material is not a composite resin. It is also not a pure ceramic. The material is a mixture of both and consists of nano-ceramic fillers. Like a composite, the material is not brittle and is fracture resistant. Like a glass ceramic, the material has excellent polish retention for lasting esthetics. The material is easily machined by chair side or in a dental lab side, could be an useful restorative option.

Crystallization Mechanism of Lithium Dislicate Glass with Various Particle Sizes (Lithium disilicate 유리의 입자크기에 따른 결정화 기구)

  • Choi, Hyun Woo;Yoon, Hae Won;Yang, Yong Suk;Yoon, Su Jong
    • Korean Journal of Materials Research
    • /
    • v.26 no.1
    • /
    • pp.54-60
    • /
    • 2016
  • We have investigated the crystallization mechanism of the lithium disilicate ($Li_2O-2SiO_2$, LSO) glass particles with different sizes by isothermal and non-isothermal processes. The LSO glass was fabricated by rapid quenching of melt. X-ray diffraction and differential scanning calorimetry measurements were performed. Different crystallization models of Johnson-Mehl-Avrami, modified Ozawa and Arrhenius were adopted to analyze the thermal measurements. The activation energy E and the Avrami exponent n, which describe a crystallization mechanism, were obtained for three different glass particle sizes. Values of E and n for the glass particle with size under $45{\mu}m$, $75{\sim}106{\mu}m$, and $125{\sim}150{\mu}m$, were 2.28 eV, 2.21 eV, 2.19 eV, and ~1.5 for the isothermal process, respectively. Those values for the non-isothermal process were 2.4 eV, 2.3 eV, 2.2 eV, and ~1.3, for the isothermal process, respectively. The obtained values of the crystallization parameters indicate that the crystallization occurs through the decreasing nucleation rate with a diffusion controlled growth, irrespective to the particle sizes. It is also concluded that the smaller glass particles require the higher heat absorption to be crystallized.

Evaluation of Mechanical Properties of Glass Substrate Strengthened by Ulatrashort Laser Pulse(1) (극초단파 레이저 강화 유리 기판의 기계적 특성평가(1))

  • Moon Pil Yong;Yoon Duk ki;Lee Kang Taek;Yoo Byung Heon;Cho Sung Hak;Ryu Bong Ki
    • Korean Journal of Materials Research
    • /
    • v.15 no.12
    • /
    • pp.796-801
    • /
    • 2005
  • In order to reduce the weight of glass in architecture, automobile, bottles, displays, a new technique that can strengthen glass was developed using various method. Generally, the strength achieved of glass-ceramics is higher as is 1.he fracture toughness by the formation of a crystalline phase inside glass. In this study, $70SiO_2-20Na_2O-10CaO-10TiO_2$ glasses were irradiated to strengthen by heterogeneous phase using femto-second laser pulse. Laser pulse irradiation of samples was analyzed by DTA, TMA, XRD, nano-indenter and SEM. Samples irradiated by laser had lower value$(3\~4\times10^{-3}Pa)$ of nano indentation which related with mother glass$(8\times10-3Pa)$ than values. Microcracks were occurred around laser irradiation area when femtosecond laser with the repetition rate of 1kHz was used as the light source to induced heterogeneous phase.

Comparative Study on the Grinded Surface Characteristics of Quartz Glass and SF-5 Glass using ELID(Electrolytic In-Process Dressing) Grinding (수정유리와 SF-5 유리의 ELID 연삭특성 비교)

  • 박상후;양동열;곽태수;오오모리히토시
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2003.06a
    • /
    • pp.94-97
    • /
    • 2003
  • A precise fabrication technology of glass is increasingly demanded fer the latest Industrial applications of spherical lenses. micro-optical components, laser applications and so on. Most of cases, the surface roughness of glass is required to be minute for improving the optical characteristics. Then. the machining characteristics of SF-5 glass and quarts glass were studied by using the ELID grinding process to get mirror surface and productivity compared with a general lapping process. A rotary type grinder with ELID generator was used to make the mirror surface of glass and a Mitutoyo surface tester and a nano-hardness tester were also used to measure the grinded surface or glass. As the results of experiments. they showed that the surface roughness(Ra) of SF-5 glass was under 7.8 nm and that of quartz glass was under 3.0 nm using the # 8000 grinder. So, the possibility of highly efficient and accurate surface for optical components can be achieved by the ELID grinding process.

  • PDF

Photo-conductive properties of CdS thin film deposited on glass substrate (글라스 기판위에 증착한 CdS 박막의 광전특성 평가)

  • Phuong, Nguyen Mai;Hur, Sung-Gi;Kim, Eui-Tae;Yoon, Soon-Gil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2007.06a
    • /
    • pp.338-338
    • /
    • 2007
  • Photo-conductive properties of CdS films deposited on glass substrates by a reactive sputtering in Ar atmosphere were characterized as a function of working pressure and the film thickness. The XRD measurements of CdS films revealed obvious (002) preferred orientation. In 300nm-thick of films, difference between dark and photo-resistance increases with increasing working pressure within the films. The films at 5 mTorr of working pressure show a dark resistance of approximately $1\;{\times}\;10^6\;{\Omega}/{\square}$ and a photo-resistance of $3\;{\times}\;10^4\;{\Omega}/{\square}$. The decrease dark- and photo-resistance of films as thickness decrease were $1.4\;{\times}\;10^6$ and $3\;{\times}\;10^4\;{\Omega}/{\square}$, respectively. CdS films deposited on glass substrates are considered tobe suitable for photo-conductivity materials in stealth radome applications.

  • PDF

Chemical Strengthening Involving Outward Diffusion Process of Na+ Ion in Iron-containing Soda-lime Silicate Glass

  • Choi, Hyun-Bin;Kang, Eun-Tae
    • Journal of the Korean Ceramic Society
    • /
    • v.52 no.2
    • /
    • pp.133-136
    • /
    • 2015
  • The outward diffusion of $Na^+$ ions in iron-bearing soda lime silicate glass via oxidation heat treatment before the ion exchange process is artificially induced in order to increase the amount of ions exchanged during the ion exchange process. The effect of the addition process is analyzed through measuring the bending strength, the weight change, and the inter-diffusion coefficient after the ion exchange process. The glass strength is increased when the outward diffusion of $Na^+$ ions via oxidation heat treatment before the ion exchange process is added. For the glass subjected to the additional process, the weight change and diffusion depth increase compared with the glass not subjected to the process. The interdiffusion coefficient is also slightly increased as a result of the additional process.