• 제목/요약/키워드: slurry materials

검색결과 508건 처리시간 0.033초

교반동력에 의한 기능성 물질 함유 수용액의 빙부착 평가 (Evaluation of Ice Adhesion in an Aqueous Solution with Functional Materials by Stirring Power)

  • 승현;백종현;홍희기;강채동
    • 설비공학논문집
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    • 제16권8호
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    • pp.720-727
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    • 2004
  • In the process of ice-slurry making, the phenomenon of ice adhesion influences extremely to ice making system. In this study, the effect on the ice adhesion by thermal storage material with additives is investigated quantitatively. Various solutions of 300 g in a stainless vessel were frozen under stirring. Through the experiment the ice adhesion between cooling wall and ice-slurry was compared with each other by measuring the stirring power. From the experiment, the stirring power in EG, SCA solution was smaller than those in the solution containing functional materials, such as poly-vinyl-alcohol or kitchen detergent.

슬러리 가압함침에 의한 3D Mullite 섬유 Preform의 알루미나 입자 충전 (Packing of Alumina Particles in 3D Preform of Mullite Fiber by Slurry Pressure-Infiltration)

  • 심수만
    • 한국세라믹학회지
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    • 제50권6호
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    • pp.528-532
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    • 2013
  • Well-dispersed slurries of submicron-sized alumina powders were pressure-infiltrated in 3D preforms of mullite fibers and the effects of the particle size and infiltration pressure on the particle packing characteristics were investigated. Infiltration without pressure showed that the packing density increased as the particle size decreased due to the reduction of the friction between the particles and the fibers. The infiltrated preforms contained large pores in the large voids between the fiber tows and small pores in the narrow voids between the individual fibers. Pressure infiltration resulted in a packing density of 77% regardless of the particle size or the infiltration pressure(210 ~ 620 kPa). Pressure infiltration shortened the infiltration time and eliminated the large pores in preforms infiltrated with the slurries of smaller particles. The slurry pressure-infiltration process is thus an efficient method for the packing of matrix materials in various preforms.

Properties of Polysiloxane Coated Borosilicate Lining Blocks

  • Song, Jeongho;Song, Ohsung
    • 한국세라믹학회지
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    • 제54권6호
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    • pp.525-529
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    • 2017
  • To improve the thermal resistance of a porous borosilicate lining block, we prepared and applied polysiloxane-fumed silica-ethanol slurry on top of the block and fired the coating layer using a torch for 5 minutes at $800^{\circ}C$. We conducted magnified characterizations using a microscope and XRD analysis to observe phase transformations, and TGA-DTA analysis to determine the thermal resistance. Thermal characterizations showed improved heat resistance with relatively high polysiloxane content slurry. Cross-sectional optical microscope observation showed less melting near the surface and decreased pore formation area with higher polysiloxane content slurry. XRD analysis revealed that the block and coating layer were amorphous phases. TGA-DTA analysis showed an endothermic reaction at around $550^{\circ}C$ as the polysiloxane in the coating layer reacted to form SiOC. Therefore, coating polysiloxane on a borosilicate block contributes to preventing the melting of the block at temperatures above $800^{\circ}C$.

소결조건이 지르콘 쉘 몰드의 기계적 특성에 미치는 영향 (Effect of Sintering condition on Mechanical Properties of Zircon Shell Molds)

  • 김재원;김두현;서성문;조창용;최승주
    • 한국재료학회지
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    • 제9권9호
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    • pp.865-871
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    • 1999
  • 지르콘 쉘 몰드를 제조하여 소결 온도 및 시간에 따른 소결거동이 기계적특성에 미치는 영향을 관찰하였다. $1000^{\circ}C$에서 1.5시간동안 소결 한 쉘 몰드의 1차 코팅 표면층에서 미세균열의 크기 및 수가 극대화되었으며 소결온도 및 시간이 증가할수록 상온강도와 기공의 비표면은 감소하였다. 1차 소결 후 $1500^{\circ}C$에서 4시간동안 소결 처리한 주형의 고온변형거동은 백업층과 하중의 역방향으로 스터코와 지르콘 슬러리의 경계면을 따라 변형이 발생하였다. 1차 코팅층에서 알루미나 스터코와 지르콘 슬러리의 열팽창계수 차이와 백업 코팅층에서 지르콘 슬러리간의 입도 차이가 고온변형시험 중 역변형을 일으킨 것으로 판단된다.

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반응소결 SiC 재료와 $SiC_f/SiC$ 복합재료의 특성 (CHARACTERIZATION OF MONOLITHIC RS-SiC AND RS-$SiC_f/SiC$ COMPOSITE MATERIALS)

  • 진준옥;이상필;이진경;윤한기
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.376-380
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    • 2003
  • The microstructure and the mechanical properties of RS-SiC and RS-$SiC_f/SiC$ materials have been investigated in conjunction with the content of residual silicon and porosity. The mechanical properties of RS-SiC materials suffered from the thermal exposure were also examined. RS-SiC based materials bave been fabricated using the complex matrix slurry with different composition ratios of SiC and C panicles. The characterization of RS-SiC based materials was investigated by means of SEM, EDS ~d three point bending test. Based on the mechanical property-microstructure correlation, the high temperature applicability of RS-SiC based materials was discussed.

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Effect of Impact Energy on the Impact-Wear Properties of High Manganese Steels in Acidic Corrosive Conditions

  • Wang, Kai;Du, Xiao-Dong;Wu, Kai;Youn, Kuk-Tae;Lee, Chan Gyu;Koo, Bon Heun
    • Corrosion Science and Technology
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    • 제7권6호
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    • pp.362-369
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    • 2008
  • The impact abrasion behavior of high manganese steel is investigated under three kinds of impact energy in acid hematite ore slurry by using a modified MLD-10 impact abrasion tester. Through the SEM observation of the worn surface and the optical metallographic analysis of the cross-sectional samples, the corrosive impact abrasion mechanisms of the steel under different impact energies are studied. In acid-hematite slurry, the variations of impact energies would result in synchronous transformation of the impact abrasion properties and mechanisms of the high manganese steel in the corrosive condition, as led different corrosive impact abrasion mechanism under different impact energies.

Cu-CMP에서 Alanine이 Cu와 TaN의 선택비에 미치는 영향 (Effect of Alanine on Cu/TaN Selectivity in Cu-CMP)

  • 박진형;김민석;백운규;박재근
    • 한국재료학회지
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    • 제15권6호
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    • pp.426-430
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    • 2005
  • Chemical mechanical polishing (CMP) is an essential process in the production of integrated circuits containing copper interconnects. The effect of alanine in reactive slurries representative of those that might be used in copper CMP was studied with the aim of improving selectivity between copper(Cu) film and tantalum-nitride(TaN) film. We investigated the pH effect of nano-colloidal silica slurry containing alanine through the chemical mechanical polishing test for the 8(inch) blanket wafers as deposited Cu and TaN film, respectively. The copper and tantalum-nitride removal rate decreased with the increase of pH and reaches the neutral at pH 7, then, with the further increase of pH to alkaline, the removal rate rise to increase soddenly. It was found that alkaline slurry has a higher removal rate than acidic and neutral slurries for copper film, but the removal rate of tantalum-nitride does not change much. These tests indicated that alanine may improve the CMP process by controlling the selectivity between Cu and TaN film.