• Title/Summary/Keyword: Melting Range

Search Result 371, Processing Time 0.022 seconds

Studies on Overglaze Stain (釉上彩色料에 關한 硏究)

  • Lee, Chong-Keun;Park, Yong-Wan
    • Journal of the Korean Chemical Society
    • /
    • v.4 no.1
    • /
    • pp.27-37
    • /
    • 1957
  • High-fire stain is influenced by the conditions of glaze, firing atmosphere, etc. On the contrary, low fire stain is not influenced by those conditions but obtainable in arbitrary colors and it is indispensable for pottery decoration. It is difficult for us to study into the color in the sphere of result publication method and expression of color. Looking over the literature on this subject, I have been confronted with much difficulties, accordingly, I made a basic and systematic experiment as to six low-firing stains (blue, green, blue-green, brown black and yellow) and made it proper to be applied in these studies. On pigment, I confirmed the influence of the assistant coloring matter by mixing up the coloring matter and the assistant coloring matter in various proportions. On flux, I measured the melting point by making PbO-$SiO_2$ system and PbO-$B_2O_3-SiO_2$ system and decided the range of usage. Also I checked the coloring by making the pigment on laze with pigment and flux manufactured, and concluded the pigment and flux adaptation to it.

  • PDF

Crystallization Behavior of $CaO.Al_2O_3.2SiO_2$ Glass with Kinetic Parameters (열분석에 의한 $CaO.Al_2O_3.2SiO_2$ 유리의 결정화 고찰)

  • 이승한;류봉기;박희찬
    • Journal of the Korean Ceramic Society
    • /
    • v.31 no.12
    • /
    • pp.1545-1551
    • /
    • 1994
  • Various kinetic parameters of the nucleation and crystallization in anorthite glass (CaO.Al2O3.2SiO2) were calculated by nonisothermal differential thermal analysis. Base glass and glass with TiO2 were prepared by melting. In base glass, the temperature where nucleation can occur ranges from 85$0^{\circ}C$ to 9$25^{\circ}C$ and the temperature for maximum nucleation was 900$\pm$5$^{\circ}C$. In glass with TiO2, the nucleation temperature range was 800~875$^{\circ}C$ and the maximum nucleation temperature was 850$\pm$5$^{\circ}C$. Kissinger equation, Bansal equation, and modified Ozawa equation were used for calculating activation energy for crystallization, Ec. The results showed the same activation energies for both glasses with and without TiO2 in the different equations. The shape of maximum exotherm peak and Ozawa equation were used for Avrami exponent, n. The n value for each glass was 2, indicating that each glass crystallized primarily by bulk crystallization.

  • PDF

Interactive VR film Storytelling in isolated space

  • Kim, Tae-Eun
    • International journal of advanced smart convergence
    • /
    • v.9 no.1
    • /
    • pp.163-171
    • /
    • 2020
  • There are many differences in narrative delivery between common movies and Virtual Reality(VR) films due to their differences in the appreciation structure. In VR films, scene changes by cuts have hindered the immersion of the audience instead of promoting narrative delivery. There are a range of experiments on narratives and immersion to solve this issue in VR films. Floating Tent applies hand gestures and immersive effects found in game elements and does not disturb narrative delivery by setting proper spaces and employing a direction technique to enable the melting of narratives into the characteristics of the spaces. There are time limits to offsound and mission performance, and devices fit for apocalyptic spatial expressions are made through a program. One of measures for the increasingly growing interactive storytelling in VR films is effective immersion. In narrative delivery, it is important to consider spatial setting and immersion to enable active intervention into events for immersion rather than passive audience only supposed to watch characters' acting.

The influence of atomosphere on high temperature crystal growth

  • Klimm, D.;Schroder, W.
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.9 no.4
    • /
    • pp.360-364
    • /
    • 1999
  • The growth of crystals with high melting point$t_{fus}$$\geq$$1600^{\circ}C$ faces the researcher with experimental problems, as the choice of materials that withstand such high t is rather limited. Many metallic construction materials are in this high t range already molten or exhibit at least a drastically reduced mechanical strength. The very few materials with$t_{fus}$$1600^{\circ}C$ as e.g. W, Mo, and partially even Ir are more or less sensitive against oxygen upon heating. Whenever possible, high t crystal growth is performed under inert atmosphere (noble gases). Unfortunately, many oxides are not thermodynamically stable under such conditions, as reduction takes place within such atmosphere. A thoroughly search for suitable growth conditions has to be performed, that are on the one side "oxidative enough" to keep the oxides stable and on the other side "reductive enough" to avoid destruction of constructive parts of the crystal growth assembly. The relevant parameters are t and the oxygen partial pressure${po}_{2}$. The paper discusses quantitatively relevant properties of interesting oxides and construction materials and wasy to forecast theri behavior under growth conditions.

  • PDF

The Thermally Resistance Strength of LAS($Li_2O$-$Al_2O_3$-$SiO_2$)System(I) ($Li_2O$-$Al_2O_3$-$SiO_2$계 소지의 내열 강화특성(I))

  • Lee, Eung-Sang;Choi, Sung-Chul;Park, Hyun;Cho, Woo-Seog
    • Journal of the Korean Ceramic Society
    • /
    • v.27 no.2
    • /
    • pp.283-287
    • /
    • 1990
  • The study was aimed at investigating sintering characteristics, the overall properties from the ternary Li2O-Al2O3-SiO2 system. This system, which was considered without additives and selected five compositions, was studied with variation of the amount of SiO2. The reactivity of the system was observed by D.T.A.. Characteristics of sintering, microstructure, property and stability of produced phase were studied. It was found that because the range of sintering was narrow and the temperature of sintering was close to the melting temperature, the sintering by the general method was difficult. Also, these linear thermal expansion coeffecients were measured.

  • PDF

Effect of Heat Setting on Physical Properties of Dyeable Polypropylene Fabric (Dyeable polypropylene 직물의 열처리에 따른 물성변화)

  • Lee, Shin-Hee
    • Fashion & Textile Research Journal
    • /
    • v.11 no.3
    • /
    • pp.481-487
    • /
    • 2009
  • The purpose of this study is to improve the defects of dyeable polypropylene(DPP) fabric by heat setting and to describe the change of physical properties of DPP fabrics. The thermosetting was carried out in autoclave from 100 to $140^{\circ}C$ temperature range for 2 min. In this study, we investigated the effect of the thermosetting temperatures on the structural, thermal, mechanical properties(e.g., the strength and elongation) and dyeability of DPP fabrics. The melting energy(J/g), the tensile strength was found to increase with increasing temperature of thermosetting. The diffraction peak at Bragg angle($2{\theta}$) about $13.8^{\circ}$ were very strong and diffraction intensity increased with increasing thermosetting temperatures. And d-spacing and half-width decreased with increasing thermosetting temperatures. On the other hand, the dyeability(K/S) and crease recovery decreased with an increasing thermosetting temperatures.

CFRP Laser Joining Computer Simulation in a Parallel Kinematic Machine (병렬가공기계용 CFRP의 레이저 용접특성 시뮬레이션)

  • Lee, Seung-Taek;Park, Seung-Gyu;Choi, Hae-Woon
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.16 no.1
    • /
    • pp.77-82
    • /
    • 2017
  • A computer simulation method is introduced to understand the joining phenomena of PC and CFRP by estimating the temperature of the weld zone. Following the prior or preliminary research, the power range was set between 3 watts and 7 watts, and the scanning speed was set at 500 mm/min and 1,000 mm/min, respectively. Based on the computer simulation, the temperature near the joining boundary was not sufficient at the scanning speed of 1,000 mm/min, regardless of the selected powers. However, the temperature increases above the melting temperature of the selected polymers at the scanning speed of 500 mm/min. The simulation results were compared with actual weld samples to validate its actual use.

Microstructures of Bonding Interfaces after Semi-Solid Brazing of Aluminum Using A357 as a Filler Metal (A357을 이용한 알루미늄 반응고 브레이징 접합 계면 특성)

  • Lee, S.Y.
    • Transactions of Materials Processing
    • /
    • v.21 no.8
    • /
    • pp.506-511
    • /
    • 2012
  • Aluminum brazing normally requires a careful control of temperature due to the small interval between brazing and melting temperatures for base materials. Unsuitable processing conditions, including brazing temperature outside admissible range, gap between brazed materials or inadequate flux feeding, can lead to joining defects. In this study, A357 was used as a filler metal for the brazing of pure aluminum base materials and brazed at temperatures in the semi-solid state. Interface microstructures with base materials were observed using optical metallography(OM) and scanning electron microcopy(SEM) with energy dispersive spectroscopy(EDS), and compared to conventional aluminum brazing.

The Effects of Thermo-mechanical Treatment on the Thixoforming Process of Cu-Ca Alloys for High Efficiency Electrical Motors (고효율 전동기용 Cu-Ca 합금의 반응고 성형공정에 미치는 가공열처리의 영향)

  • Lee, E.Y.;Kang, B.M.;Lee, S.Y.
    • Journal of the Korean Society for Heat Treatment
    • /
    • v.16 no.5
    • /
    • pp.267-274
    • /
    • 2003
  • The effect of the thermo-mechanical treatment on the microstructural development and the electric conductivity of Cu-Ca alloys are studied for the thixoforming processed rotor of the induction motor The Cu-Ca alloys containing Ca less than 1.0wt% show the electrical conductivity higher than 80% IACS They also show broad melting range over $150^{\circ}C$ which is desirable for the thixoforming process The semi-solid microstructure of cast alloy changes from the dendrite structure to globular structure by prior deformation before reheating. The details of microstructural changes by the thermo-mechanical treatment are discussed.

Operating characteristics of high Tc superconducting current limiting fuse at various voltages (고온 초전도 한류퓨즈의 전압별 동작특성)

  • Choi, Hyo-Sang;Hyun, Ok-Bae;Kim, Hye-Rim;Hwang, Si-Dole;Park, Kwon-Bae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2001.05c
    • /
    • pp.161-163
    • /
    • 2001
  • We present the basic properties of a superconducting current limiting fuse (SCLF) based on YBCO/Au films. The SCLFs consists of YBCO stripes covered with Au layers for current shunt. Under the source voltage of 100 $V_{rms}$, the longer the duration time of fault current was, the shorter its discharge time was. The duration time of fault current and its discharge time were reduced by increased voltages in the range of 200 - 300 $V_{rms}$. We thought that this was because the quench propagation was limited by local melting generated with higher voltage.

  • PDF