• 제목/요약/키워드: Metal Polish

검색결과 17건 처리시간 0.025초

은제 행정박물의 표면 클리닝에 적용되는 금속광택제 실험연구 (An Experimental Study of Metal Polishes Applied on Surface Cleaning of Silver Metal Archival Objects)

  • 조하늬;조남철
    • 보존과학회지
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    • 제30권2호
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    • pp.157-168
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    • 2014
  • 본 연구는 행정박물 보존 처리에서 자주 사용되고 있는 금속 광택제 중 3 종 (Polish T, H, C)을 선정하여 은표면의 황색 변색층을 효과적으로 제거함과 동시에 표면의 손상을 최소화하며, 광택제에 함유된 변색 억제 성분 (tarnish inhibitor)의 성능을 비교하여 보존성이 가장 우수한 광택제를 알아보고자 하였다. 실험 결과, 광택제 C를 사용하여 면봉 및 린트-프리 와이프로 세정한 시편들이 균일한 표면의 표출과 최소의 손상을 가져온다는 결과를 얻었으며 부식층 제거에도 뛰어난 결과를 보임을 확인할 수 있었다. 또한 광택제 처리 후 변색 억제 필름이 형성 되어도 변색 현상을 완벽히 방지할 수 없지만 그 중에서도 광택제 C가 자외선과 황변에 가장 안정한 것으로 나타났다. 접촉각 측정 결과에서도 소수성 및 분산 성질이 광택제 T와 광택제 H보다 상대적으로 우수한 특성을 보였다. 본 실험을 통해 현재 은제 행정박물 보존 처리에 사용되는 광택제 중에서 광택제 C가 황변 및 표면 특성이 가장 우수한 성능을 보임을 확인할 수 있었다.

SUBLAYER THICKNESS DEPENDENCE OF THE OPTICALPROPERTIES OF NI/TI AND Fe/Zr MULTILAERS

  • Lee, Y.P.;Kim, K.W.;Lee, G.M.;Rhee, J.Y.;Szymansky, B.;Dubowik, J.;Kucherenko, A.Yu.;Kudryavstev, Y.V.
    • 한국진공학회지
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    • 제6권S1호
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    • pp.70-74
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    • 1997
  • The study of the thickness dependence of the electron energy structure of Fe, Ni, Ti and Zr sublayers in Ni/Ti and Fe/Zr multilayers by using the experimental and computer simulated optical spectroscopy has been performed. A series of Ni/Ti and Fe/Ze multiayered films (MLF) with a bilayer period of 0.5 - 30 nm and constant (Ni/Ti) / different (Fe/Zr) sublayer thickness ratios were prepared by using computer-controlled double-pair target face-to-face sputtering onto a glass substrate at room temperature (RT) Computer simulation of the resulting optical properties of these MLF was carried out by solving of multireflection problem with a matrix method assuming either "sharp" interfaces resulting in rectangular depth profiles of the components or "mixed" (alloy-like) interfaces of variable thickness between pure-metal sublayers. Optical constants of pure bulk metals as well as equiatomic alloy interfaces were employed in these simulations. It was shown that the difference between experimental and simulated optical properties of the investigated MLF increases with decrease in sublayer thickness. This result allows to conclude that the electronic structures of sublayers below 4-5 nm thickness in mlf differ from the corresponding bulk metals.ponding bulk metals.

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Physical properties of ion-beam mixed Fe/Si multilayered films

  • Park, J.S.;Kim, C.O.;Lee, Y.P.;Kudryavtsev, Y.V.;Dubowik, J.;Szymanski, B.;Rhee, J.Y.
    • Journal of Korean Vacuum Science & Technology
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    • 제5권2호
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    • pp.38-42
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    • 2001
  • We investigated physical properties of ion-beam mixed Fe/si multilayerd films(MLF) prepared by rf sputtering onto glass substrates at room temperature. Such an ion-beam treatment has led to noticeable changes in the structural and physical properties of the MLF: the formation of a new phase which is characterized by a crystalline silicide with a low coercivity and Tc = 550 K. In contrast to the as-prepared state, the ion-beam mixed MLF contains two magnetic phases. One of them is a very soft (Hc < 2 Oe), but microscopically homogeneous one with M$\sub$eff/=6.7 kG.

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MR fluid를 이용한 알루미늄 표면의 초정밀 연마 방법 (A Study on the Ultra Precision Polishing Method of Aluminum Surface Using MR Fluids)

  • 임동욱;김병찬;홍광표;조명우
    • Design & Manufacturing
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    • 제11권2호
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    • pp.20-24
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    • 2017
  • Recent industrial developments are constantly advancing, and rapid technological development is demanding high technology level in related fields. The need for polishing is increasing even more to improve quality. In order to improve the surface quality, the final finishing process or polishing process is a very important part. Research on super precise polishing method using MR fluid is actively being carried out in domestic and foreign countries. Fine magnetic abrasive grains are aligned in the direction of a magnetic force line formed by a magnetic field and serve as a brush to polish a metal surface. This method has the advantage that the shape of the tool is not fixed and is not affected by the shape of the workpiece or the machining area. We will design the electromagnets for the MR polish polishing system and apply the magnetic field analysis using the magnetic field analysis program (ANSYS). The data obtained through this process suggests an efficient method to increase the magnetic flux density important for polishing. We will investigate the influence of the Al6061-T6 specimen on the surface of the MR polishing machine based on the optimized design.

미세공구와 자기체인구조를 이용한 초정밀 폴리싱 특성 (Nano-scale Precision Polishing Characteristics using a Micro Quill and Magnetic Chain Structure)

  • 박성준;안병운;이상조
    • 한국정밀공학회지
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    • 제21권8호
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    • pp.34-42
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    • 2004
  • A new polishing technique for three dimensional micro/meso-scale parts is suggested using a micro quill and a magnetic chain structure. The principle of this method is to polish the target surface with the collected magnetic brushes at a micro tool by the non-uniform magnetic field generated around the tool. In a typical magnetic abrasive finishing process magnetic particles and abrasive particles are unbonded each other. But, to finish the three dimensional small parts bonded magnetic abrasive have to be used. Bonded magnetic abrasives are made from direct bonding, and their polishing characteristics are also examined. Alumina, silicon carbide and diamond micro powders are used as abrasives. Base metal matrix is carbonyl iron powder. It is found that bonded magnetic abrasives are superior to unbonded one by experiment. finally, the polished surface roughness is evaluated by atomic force microscope.

방전가공된 공구강표면의 연마재 유동가공에 관한 연구 (A Study of Abrasive Flow Machining on EDMed Surfacs of Tool Steel)

  • 최재찬;김창호;허관도
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.8-13
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    • 1996
  • A relatively new non-traditional finishing process called Abrasive Flow Machining(AFM) is being used to deburr, polish and radius workpiece or produce compressive residual stresses by flowing an abrasive-laden viscoelastic compound across the surface to be machined. This paper presents the effects of AFM on surfaces of tool steel produced by EDM and W-EDM. Using AFM, white layer produced by EDM is erased almost equally and the amount of metal removal is significantly affected the initally machined surface condition of workpiece. The dimension of workiece is enlarged and its surface roughness is improved as AFM time is increased. The optimal AFM time can be established from the experimental results. It is considered that the grinding method lide AFM is useful to grind complex or slim geometry of workpiece even. Scanning Electron Microscopy(SEM) was used to study the surface characteristics of the workpiece before and after AFM.

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Ferromagnetic Resonance Observation of Martensitic Phase Transformation in Ni-Mn-Ga Ferromagnetic Shape Memory Films

  • Dubowik, J.;Kudryavtsev, Y.V.;Lee, Y.P
    • Journal of Magnetics
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    • 제9권2호
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    • pp.37-39
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    • 2004
  • Polycrystalline Ni-Mn-Ga films have been deposited onto mica substrates held at 720 K by flash-evaporation method. At room temperature the films have a tetragonal structure with a = b = 0.598 and c = 0.576 nm typical for bulk $Ni_2MnGa$ below a martensitic transformation. Temperature measurements of ferromagnetic resonance reveal a martensitic phase transformation at 310 K. The transformation brings about a substantial decrease in the effective magnetization and a drastic increase in the ferromagnetic resonance linewidth due to a strong increase in the magnetic anisotropy in the martensitic phase.

IBAD template용 니켈 합금의 연속 전해연마 (Reel-to-reel electropolishing of Ni alloy tapes for IBAD template)

  • 하홍수;김호겸;고락길;김호섭;송규정;박찬;유상임;주진호;문승현
    • Progress in Superconductivity
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    • 제6권1호
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    • pp.69-73
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    • 2004
  • Ni alloy tape is electropolished to be used as a metal substrate for fabrication of IBAD (ion-Beam Assisted Deposition)-MgO texture template fur HTS coated conductor. Electropolishing is needed to obtain a very smooth surface of Ni alloy tape because the in-plane texture of templates is sensitive to the roughness of metal substrate. The critical current of YBCO coated conductor depends on the texture of YBCO that depends on the texture of the IBAD MgO layer. And so the smoothness of the metal substrate is directly related to the superconducting properties of the coated conductor. In this study, we have prepared a reel-to-reel electropolishing apparatus to polish the Ni alloy tapes for IBAD. Various electropolishing conditions were investigated to improve the surface roughness. Hastelloy tape is continuously electropolished with high polishing current density (0.5 ∼ 2 A/$\textrm{cm}^2$) and fast processing time (1 ∼ 3 min). Polished hastelloy tapes have surface roughness(RMS) of below 1 nm on a 5 ${\times}$ 5 $\mu\m^2$ from AFM and SEM.

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