• Title/Summary/Keyword: Optimum heat-treatment temperature

Search Result 246, Processing Time 0.03 seconds

Effect of Annealing Heat Treatment to Corrosion Resistance of a Copper (구리의 내식성에 미치는 어닐링 열처리의 영향)

  • Kim Jin-Kyung;Moon Kyung-Man;Lee Jin-Kyu
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.29 no.6
    • /
    • pp.654-661
    • /
    • 2005
  • Copper is a well known alloying element that is used to improve the resistance to general corrosion of stainless steel And also Cu cation have the anti-fouling effect to inhibit adhesion of the marine algae and shellfish to the surface of heat exchanger cooling pipe or outside wall of the ship, Therefore there are some anti-fouling methods such as anti-fouling Paint mixed with copper oxide or MGPS(Marine Growth Preventing System) by using Cu cation dissolved to the sea wather solution. Cu cation can be dissolved spontaneously by galvanic current due to Potential difference between Cu and cooling pipe of heat exchanger with Ti material, which may be one of the anti-fouling designs. In this study the effect of annealing heat treatment to galvanic current and Polarization behavior was investigated with a electrochemical points of view such as measurement of corrosion Potential, anodic polarization curve. cyclic voltammetric curve, galvanic current etc The grain size of the surface in annealed at $700^{\circ}C$ was the smallest than that of other annealing temperatures. and also the corrosion Potential showed more positive potential than other annealing temperatures. The galvanic current between Ti and Cu with annealed at $700^{\circ}C$ was the largest value in the case of static condition. However its value in the case of flow condition was the smallest than the other temperatures. Therefore in order to increase anti-fouling effect by Cu cation, the optimum annealing temperature in static condition of sea water is $700^{\circ}C$, however non- heat treated specimen in the case of flow condition may be desirable.

Determination of Heat Killing Temperature of Alfalfa (Medicago sativa L.) (알팔파(Medicago sativa L.)의 치사온도 결정)

  • 김기용;강경민;성병렬;김맹중;임용우;김원호;박근제;이병현
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.24 no.1
    • /
    • pp.21-24
    • /
    • 2004
  • To determine lethal temperature of alfalfa (Medicago sativa L. cv Vernal) at heat-stressed conditions, seedlings grown in a small pots for 4 weeks were subjected to different temperature regimes of heat treatment. No apparent demage was observed when the plants were treated at 45, 50 or $60^{\circ}C$ for 1 h. Heat treatments at 60 and $65^{\circ}C$ for 1 h, several plants were withered and showed damage symptom on their leaves. When the plants were exposed to $70^{\circ}C$ for 1 h, most of leaves were severely withered, but it was not lethal conditions for the whole plants. By contrast, most of plants were died within one day after heat treatment at $80^{\circ}C$ for 1h. Furthermore, plants exposed to $80^{\circ}C$ for 50 min were also died within 7 days. It was found that new shoots were regenerated from the plants that had been treated at $80^{\circ}C$ within 45 min. These results indicate that heat treatment at $80^{\circ}C$ for 50 min is an optimum condition to distinguish the lethality of alfalfa plants. Simple viability assay system established in this study will be useful fer selection and characterization of heat-tolerant transgenic alfalfa plants.

The Study on the Denuded Zone Formation of Czochralski-grown Single Crystal Silicon Wafer (I) (Czochralski 법으로 성장시킨 단결정 Silicon Wafer에서의 표면 무결함층(Denuded Zone) 형성에 관한 연구(I))

  • 김승현;양두영;김창은;이홍림
    • Journal of the Korean Ceramic Society
    • /
    • v.28 no.6
    • /
    • pp.495-501
    • /
    • 1991
  • This study is intended to make defect-free region, denuded zone at the silicon wafer surface for semiconductor device substrates. In this experiment, initial oxygen concentration of starting material CZ-grown silicon wafer, various heat treatment combinations, denuding ambient and the amounts of oxygen reduction were measured, and then denuded zone (DZ) formation and depth were investigated. In Low/High anneal (DZ formation could be achieved), the optimum temperature for Low anneal was 700$^{\circ}C$∼750$^{\circ}C$. In case of High anneal, with the time increased, DZ depth was increased at 1000$^{\circ}C$, 1150$^{\circ}C$ respectively, but on the contrary, DZ depth was decreased at low temperature 900$^{\circ}C$. As well, out-diffusion time below 2 hours was unsuitable for effective Gettering technique even though the temperature was high, and DZ formation could be achieved when initial oxygen concentration was only above 14 ppm in silicon wafer.

  • PDF

Studies on Transfer Printing of Cotton and Polyester/Cotton Blended Fabrics Treated with Water Soluble Polyurethane Resin (수용성 폴리우레탄 수지 처리된 면 및 폴리에스테르/면 혼방직물의 전사날염에 관한 연구)

  • 황종호;전병익
    • Textile Coloration and Finishing
    • /
    • v.11 no.5
    • /
    • pp.13-21
    • /
    • 1999
  • In this study, selected cotton fabrics and polyester/cotton(P/C) blended fabrics are treated with a soluble polyurethane(SPU) and then, printed by heat transfer to determine the effect of SPU treatment on dye uptake of the samples. The results obtained are as follows: 1) In heat transfer, dye-uptake gets higher in Vopotion to temperature and time. The optimum printing temperature and printing time of C.I. Disperse Orange 3 and C.I. Disperse Violet 1 are $200^\circ{C}$ and 50sec. 2) Dye-uptake gets higher according to SPU concentration ; both cotton and P/C fabrics show the highest at $100g/\ell$. 3) In color, as temperature, time and SPU concentration increase, P/C fabrics show more yellowish orange color than cotton fabrics in case of C.I. Disperse Orange 3 and P/C fabrics show more reddish violet color than cotton fabrics in case of C.I. Disperse Violet 1. 4) All fastness of cotton and P/C fabrics treated with SPU are good, but color fastness to washing and water of cotton fabrics treated with SPU are not good.

  • PDF

Tensile properties and Spot Weldability of Trip High Strength Steel Sheet (Trip형 고장력강판의 인장성질 및 점용접성)

  • Kang, C.Y.;Kim, H.J.;Kim, C.G.;Lee, B.W.;Lee, M.Y.;Lee, G.H.;Kim, T.I.
    • Journal of the Korean Society for Heat Treatment
    • /
    • v.11 no.4
    • /
    • pp.295-304
    • /
    • 1998
  • The effects of retained austenite and carbon content in the retained austenite on the tensile strength-elongation balance and spot weldability of TRIP high strength steel sheet have been investigated. The retained austenite of granular type increased with increasing intercritical annealing and austempering temperature, and film type was increased with the increase of austempering time. The volume fraction of retained austenite increased with decreasing intereritical annealing temperature, and the maximum value was obtained at austempering temperature of $400^{\circ}C$. The values of tensile strength-elongation balance increased with decreasing intercritical annealing temperature and maximum value was obtained at austempering temperature of $400^{\circ}C$. The maximum value of tensile strength-elongation balance was obtained at a retained austenite content of about 12%. Tensile shear strength of the specimens with retained austenite was higher than that of the normalizing specimens. With increasing welding current and time, the tensile shear strengh and nugget diameter increased, while nugget thickness showed the peak value and then decreased. The optimum range of welding condition at the given welding pressure of 350kgf was 7~11kA and 10~15 cycles.

  • PDF

The Effect of Low Melting Point Phase on Mechanical Properties of Al-Cu-Li-X(In, Be) Alloys (Al-Cu-Li-X(In, Be) 합금의 기계적 성질에 미치는 저융점상의 영향)

  • Lee, J.S.;Lee, S.H.;Kim, S.W.;Woo, K.D.
    • Journal of the Korean Society for Heat Treatment
    • /
    • v.8 no.4
    • /
    • pp.245-254
    • /
    • 1995
  • The purpose of this study was to examine the effects of low melting point phase(LMPP) on mechanical properties in the Al-Cu-Li-X(In, Be) alloys. This study was performed by the differential scanning calorimetry(DSC), the transmission electron microscope(TEM), hardness test, tensile test and notch tensile test. The shape of LMPP in the specimens homogenized at $570^{\circ}C$ was film type due to remelting at grain boundary during homogenization. Low melting point phases had no effects on mechanical properties in the aging treated materials, because the density of LMPPs was low. Mechanical properties of the aging treated materials were affected by the density of matrix precipitation phases and grain sizes. For the In or In, Be added Al-Cu-Li alloys, the optimum solution treatment temperature was $550^{\circ}C$. The strength of Al-Cu-Li-In-Be $T_6$ treated alloy was higher than that of 2090-$T_8$ alloy.

  • PDF

Characterization analysis of $CuInS_2$ absorber layer grown by heat treatment of low temperature (저온에서 열처리한 $CuInS_2$ 광흡수층 박막 특성분석)

  • Yang, Hyeon-Hun;Back, Su-Ung;Kim, Han-Wool;Han, Chang-Jun;Lee, Suk-Ho;Jeong, Woon-Jo;Park, Gye-Choon;Lee, Jin;Chung, Hae-Deok
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2010.06a
    • /
    • pp.98.2-98.2
    • /
    • 2010
  • $CuInS_2$ thin films were synthesized by sulfurization of Cu/In Stacked elemental layer deposited onto glass Substrates by vacuum furnace annealing at temperature 200[$^{\circ}C$]. And structural and electrical properties were measured in order to certify optimum conditions for growth of the ternary compound semiconductor $CuInS_2$ thin films with non-stoichiometry composition. $CuInS_2$ thin film was well made at the heat treatment 200[$^{\circ}C$] of SLG/Cu/In/S stacked elemental layer which was prepared by thermal evaporator, and chemical composition of the thin film was analyzed nearly as the proportion of 1 : 1 : 2. Physical properties of the thin film were investigated at various fabrication conditions substrate temperature, annealing and temperature, annealing time by XRD, FE-SEM and hall measurement system. At the same time, carrier concentration, hall mobility and resistivity of the thin films was $9.10568{\times}10^{17}$ [$cm^{-3}$], 312.502 [$cm^2/V{\cdot}s$] and $2.36{\times}10^{-2}$ [${\Omega}{\cdot}cm$], respectively.

  • PDF

Effects of the Heat Treatment Temperature and Thickness of YBCO Film Fabricated by TFA-MOD Method (TFA-MOD법을 이용한 YBCO 박막의 열처리 온도와 두께의 영향)

  • Jang Seok-Hern;Lim Jun-Hyung;Lee Jin-Sung;Yoon Kyung-Min;Kim Kyu-Tae;Joo Jin-Ho;Kim Chan-Joong;Nah Wan-Soo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.19 no.5
    • /
    • pp.467-476
    • /
    • 2006
  • We fabricated the YBCO films on LAO substrate using the TFA-MOD method and evaluated the effects of heat treatment temperature and film thickness on the microstructure, degree of texture, and critical properties. The calcining and firing were peformed at the temperature range of $370^{\circ}C-460^{\circ}C\;and\;750^{\circ}C-800^{\circ}C$, respectively. For the films fired at $775^{\circ}C$ after calcining at $400^{\circ}C-430^{\circ}C$showed highest critical temperature (Tc-onset) of 89.5 K and critical current (Ic) of 40A/cm-width which corresponds to critical current density (Jc) of $1.8MA/cm^2$. The highest critical properties are probably attributed to the formation of purer YBCO phase, stronger biaxial texture, and higher oxygen content, according to the XRD, pole-figure, SEM, Raman analysis. From the multi-coated films, the Ic increased from 39 to 169 A/cm-width as the coating repeated to four times, while the corresponding Jc was measured from once to be in the range of $0.8-1.2MA/cm^2$. Both Ic and Jc degraded as the coating repeated further, indicating that the optimum thickness is in the range of $1.0{\mu}m-1.7{\mu}m$.

Optical properties of (CexLu1-x)3MgAl3SiO12 yellow phosphor ((CexLu1-x)3MgAl3SiO12 황색 형광체의 광학적 특성)

  • Lee, Jung-Il;Kim, Tae Wan;Oh, Ho Ra;Hong, Chang Woo;Ryu, Jeong Ho
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.26 no.1
    • /
    • pp.14-18
    • /
    • 2016
  • A novel $Ce^{3+}$ doped $(Ce_xLu_{1-x})_3MgAl_3SiO_{12}$ phosphor was successfully synthesized by a conventional solid-state reaction. Heat-treatment temperature was controlled from 1250 to $1550^{\circ}C$ for 5 h. XRD and PL properties were analyzed for the optimum heat-treatment condition. Ce doping concentration was varied from 2.0 to 10.0 mol% for the optimum Ce doping concentration. The PL intensity, peak wavelength and FWHM were calculated with the Ce doping concentration, and evaluated for the application to LED packaging. Particle size and morphology were also characterized for synthesized phosphor sample at optimum heat-temperature and Ce doping concentration.

A Study on the Properties of Silk and Nylon 6 Fabrics by Tannic Acid Treatment

  • Yoa, Soojin;Kim, Jongjun
    • Journal of Fashion Business
    • /
    • v.20 no.3
    • /
    • pp.119-132
    • /
    • 2016
  • Weighting of silk fabrics have long been practiced in silk fabric trading based on the primary consideration of price-weight, and secondary one of quality improvement in handle, luster, and drape properties. Recent trend of practicing weighting of silk fabrics is, however, focused on the improvement of the handle, luster, drape, and other properties. During the finishing processes of synthetic fiber, nylon, comprising amide structure, include the use of tannic acid, especially in the dyeing. A multitude of studies are being implemented in terms of improving fastness to washing, fastness to light of dyed nylon product, or the light fastness of nylon 6 itself. In this study, the effects of various tannic acid treatments on the physical properties related to the handle of nylon 6 and silk fabrics are examined and reviewed. The effects of treatment condition of the tannic acid, e.g., the concentration of the aqueous tannic acid solution, treatment time, and temperature were investigated. As the concentration of the aqueous solution of tannic acid increased, the bending rigidity values of the silk and nylon 6 fabrics increased. The treated fabrics felt stiff to the touch. Within the mild conditions of bending employed in the bending measurement of KES, nylon 6 treated fabric specimen exhibited a trend of improvement of bending resiliency within the range of small bending deformation. The weight of treated fabrics have all increased. The air-permeability values decreased as the treatment concentration increased. However, the decrease tendency of air permeability values may be alleviated by adjusting the fabric count during the tentering or expanding processes, either by tension adjustment or heat treatment. Optimum conditions of the treatment for nylon 6 are 1.25% tannic acid concentration, bath temperature of $85^{\circ}C$, pH 3.1, and those for silk fabric treatment are 1.25% tannic acid concentration, bath temperature of $85^{\circ}C$, pH 3.1. The treatment conditions will lead to the improvement in the properties of fabrics for summer.