• 제목/요약/키워드: Solidification Process

검색결과 501건 처리시간 0.034초

반복압출 공정을 이용한 금속분말의 미세조직 제어 (Microstructure Control of Mg Alloy Powder Using a Repeated Extrusion Process)

  • 김정곤;최한신;김택수
    • 한국분말재료학회지
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    • 제16권6호
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    • pp.438-441
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    • 2009
  • Mg-Cu composites were successively fabricated using a combination of rapid solidification and extrusion processes. In addition, the microstructural variation of the composite was investigated by performing the extrusion repeatedly. It resulted that the composite formed an uniform and dense structure by the extrusion, and the microstructure became fine as the extrusion conducted repeatedly. The microstructural variation was known to be dependent on the number of extrusion and the area reduction ratio. The tensile strength was also measured as a function of the microstructural variation.

삼면(三面)L-형(型) 주물(鑄物)의 주형내응고특성(鑄型內凝固特性)에 관(關)한 연구(硏究) (A Study on the Solidification Characteristics of 3-PLane L-Sections Castings in the Mold)

  • 한윤희;이계완
    • 한국주조공학회지
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    • 제5권4호
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    • pp.283-288
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    • 1985
  • The melt of highly purified Zn was poured by top pouring process into the open green sand mold, that was made by using the 3-plane L-sections pattern. After skin was formed, the unsolified melt was poured out by rolling-over. The thicknesses of skin for each different of castings were investigated with one dimension. The results obtained and could be summerzed as follows: 1) While the 3-plant L-sections castings were solidifying in the mold, solidification blocks of different section modulus in the castings were formed, i.e. 1-dimension divergency block, 2-dimension heat divergency block, 3-dimension heat divergency block, 2-dimension heat convergency block, and 3-dimension heat convergency block. 2) When the chill plate was set up to the mold in order to change section modulus artificially, heat divergency blocks and heat convergency blocks according to the shape of chill plate were revealed.

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새로운 응고 모델을 적용한 Czocgralski 단결정 성장 공정 모사 (The Transient Simulation of Czochralski Single Crystal Growth Process Using New Solidification Model)

  • 이경우;윤종규
    • 한국결정성장학회지
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    • 제1권1호
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    • pp.74-81
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    • 1991
  • Czochralski 단결정 성장계에서 유체동의 표면 복사열전달을 고려하여 온도분포를 모사하였다. 복사열전달 고려시 표면요소들의 view factor를 고려하였다. 고-액의 2상은 고상에 가상적으로 매우 큰 점성을 부여하여 연속의 단상으로 처리하였으며 응고시 잠열은 반복열량 방출법을 개발하여 처리하였다. 본 연구에서 개발한 응고 모델을 증명하기 위하여 Ca 금속의 용융에 적용하여 실험결과와 비교한 결과 잘 맞는다는 것을 알아낸 후 본 모사 프로그램을 Cz계에서 Al금속의 단결정 성장에 적용하였다.

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일방향 응고시킨 Al-Fe-Ni, Al-Fe-B 합금의 기계적 성질 및 조직 (The structure and mechanical properties of unidirectionally solidified Al-Fe-Ni, Al-Fe-B alloy)

  • 김여원;신문교
    • Journal of Advanced Marine Engineering and Technology
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    • 제10권4호
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    • pp.57-66
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    • 1986
  • The microstructure and mechanical properties of unidirectionally solidified Al-Fe-Ni and Al-Fe-B alloys have been studied in varying the some conditions. To investigate the change of microstructure and mechanical properties was carried out by the varying the composition and solidification rate from 1.2 to 80 mm/min at temperature gradient 60 .deg. C/cm. The results obtained are as follow; 1. In proportion to the increase of the solidification rate, the type of crystallized phase of these composite alloys was changed by added element. a) The crystallized phase of composite alloy in added nikel was changed from the rod-type fiber to platetype fiber. b) The crystallized phase of composite alloy in added boron was changed from the plate-type fiber to rod-type fiber. 2. The strength was rapidly increased with the changing process of crystallized fiber from the plate-type fiber to the rod-type.

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접촉열저항이 있는 수직벽에서의 응고과정 해석 (Analysis of the Solidification Process at a Vertical Wall With Thermal Contact Resistance)

  • 이진호;모정하;황기영
    • 대한기계학회논문집
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    • 제19권1호
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    • pp.193-201
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    • 1995
  • The role of thermal contact resistance between a casting and a metal mold as well as natural convection in the melt during solidification of a pure metal is numerically studied. Numerical simulation is performed for a rectangular cavity using the coordinate transformation by boundary-fitted coordinate and pure aluminum is used as the phase- change material. The influences of thermal contact resistance on the interface shape and position, solidified volume fraction, temperature field and local heat transfer are investigated.