• 제목/요약/키워드: Hot pressing

검색결과 582건 처리시간 0.035초

A design of ANFIS controller through ES algorithm for disturbances rejection in Hot Rolling

  • Jaekyung Jung;Ohmin Kwon;Lee, Sangmoon;Sangchul Won
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.374-374
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    • 2000
  • In this paper, we developed an ANFIS controller through ES algorithm for disturbances rejection in Hot Rolling. The looper of a Hot Rolling is installed between each pair of stands and plays key roles to enhance the product quality of the strip by controlling the tension and the width of the strip. At the same time, the AGC on top of the Mill produces a strip with the desired thickness through pressing its Mill. Between both, however, interactions are caused by coupling effects among strip tension, looper angle and strip thickness. In addition, in case disturbances, it is more difficult to keep strip quantities desirable. So we present an ANFIS controller through ES algorithm which is able to identify fuzzy rule with input/output data and update itself through output errors.

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비정질 $AI_{85}Ni_{10}Y_{5}$ 합금 리본의 벌크화와 어닐링에 따른 기계적 특성 (Bulk Processing of an Amorphous $AI_{85}Ni_{10}Y_{5}$ Alloy Ribbon and Mechanical Properties by Annealing Treatment)

  • 고병철;김종현;유연철
    • 소성∙가공
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    • 제8권6호
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    • pp.626-633
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    • 1999
  • $Al_{85}Ni_{10}Y_5$ (at. %) amorphous alloy ribbons have been produced by rapidly solidification process and consolidated by the conventional powder metallurgy method. The grains with ∼90 nm were obtained in the Al85Ni10Y5 alloy extrudates by hot-pressing followed by hot-extusion. To investigate the effect of heat treatment on microstructural change of the extrudates, heat treatment was carried out from 200℃ to 400℃ at the step of 50℃. In addition, mechanical properties of the extrudates were analysed from torsion test at the temperature range or 400∼500℃ under a strain rates of 0.2, 0.5, and 1.0/sec. The extrudates showed a flow stress of ∼190 MPa and low elongation of ∼150% at 400℃, contributing to the enhancement of ductility and hardness for extrudates. Also, grain boundary sliding was occurred in the $Al_{85}Ni_{10}Y_5$ alloy during hot deformation.

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A Oen-step Hot-forming Process for the Preparation of Anisotropic Nd-Fe-B Based Magnets

  • Yang, Jung-Pil
    • Journal of Magnetics
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    • 제2권3호
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    • pp.67-71
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    • 1997
  • A new hot-forming process has been studied to produce anisotropic Nd-Fe-B based magnets from melt-spun ribbons. The ribbon fragments were inserted in a Cu tube and hot-deformed together with one-stroke. At a height reduction ratio of 0.44, the melt-spun ribbons were densified into a magnet with a density of 7.14 g/cm3, and showed a (BH)max of 14.6 MGOe. With further deformation, the magnets were plastically deformed with Cu tubes in the lateral direction, and crystallographic anisotropy was introduced. The magnets with a height reduction ratio of 0.75 exhibited magnetic properties of (BH)max = 32.1 MGOe, Br = 11.7 kG, and iHc = 10.6 kOe. This process shows the possibility that the conventional hot-pressing and subsequent die-upsetting for anisotropic magnets can be simplified into a one-step process.

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핫프레스 및 다이업셋한 미슈레탈-페로보론 영구자석에 관한 연구 (Hot-Pressed and Die-Upset Mischmetal-Ferroboron Permanent Magnets)

  • 고관영;;조성국;최원정;김상길
    • 소성∙가공
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    • 제10권1호
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    • pp.30-34
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    • 2001
  • The magnetic and metallurgical characteristics of Mischmetal(MM) -Ferroboron (FeB) Permanent magnets have been investigated by X-ray diffractometer, scanning and transmission electron microscope and vibrating sample magnetometer under hot-pressing and die-upsetting process. The best magnetic properties obtained in these studies were $H_c$=5.8 kOe, $B_r$=5.0 kG with $(BH)_{max}=7.6 MGOe for melt-spun ribbons, $H_c$=3.0 kOe, $B_r$=4.6 kG with $(BH)_{max}$=2.9 MGOe for hot-pressed magnets and $H_c$=1.8 kOe, $B_r$=5.5 kG with $(BH)_{max}$=4.1 MGOe for die-upset magnets. The higher magnetic properties in die-upset magnets were resulted from alignment of the c-axis along the die-upsetting direction.

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Fabrication of Pt-MWNT/Nafion Electrodes by Low-Temperature Decal Transfer Technique for Amperometric Hydrogen Detection

  • Rashid, Muhammad;Jun, Tae-Sun;Kim, Yong Shin
    • 전기화학회지
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    • 제17권1호
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    • pp.18-25
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    • 2014
  • A Pt nanoparticle-decorated multiwall carbon nanotube (Pt-MWNT) electrode was prepared on Nafion by a hot-pressing at relatively low temperature. This electrode exhibited an intricate entangled, nanoporous structure as a result of gathering highly anisotropic Pt-MWNTs. Individual Pt nanoparticles were confirmed to have a polycrystalline face-centered cubic structure with an average crystal size of around 3.5 nm. From the cyclic voltammograms for hydrogen redox reactions, the Pt-MWNT electrode was found to have a similar electrochemical behavior to polycrystalline Pt, and a specific electrochemical surface area of $2170cm^2mg^{-1}$. Upon exposure to hydrogen analyte, the Pt-MWNT/Nafion electrode demon-strated a very high sensitivity of $3.60{\mu}A\;ppm^{-1}$ and an excellent linear response over the concentration range of 100-1000 ppm. Moreover, this electrode was also evaluated in terms of response and recovery times, reproducibility, and long-term stability. Obtained results revealed good sensing performance in hydrogen detection.