• 제목/요약/키워드: mechanical property

검색결과 3,512건 처리시간 0.033초

0.19C - 1.17Cr 강의 냉간인발조직과 기계적 성질 (The Microstructure and Mechanical Property of 0.19C-1.17Cr Steel with Cold Drawing)

  • 신정호;장병록
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2001년도 제4회 압출 및 인발가공 심포지엄
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    • pp.85-90
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    • 2001
  • The microstructure and mechanical property of 0.19C-1.17Cr steel were investigated with cold drawing. This commercial steel has the microstructure that is consist of ferrite and pearlite. The tensile and yield strength are increased as the reduction ratio of cold drawing is increased. It was clear that mechanical properties could be improved by combination of the heat treatments and reduction ratio. Yield strength. tensile strength, and impact value were formulated as a constitutive function of cold drawing ratio, respectively.

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유기물 첨가에 의한 전해동박의 특성 (Properties of electrodeposited copper foil by organic compounds)

  • 이관우;노승수;최창희;김상겸;손성호;문홍기;박대희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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    • pp.88-91
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    • 2001
  • The mechanical properties and surface luminous intensities of copper foil have been studied with variation of the amount of additives into the electrolyte. Especially, organic compound of HEC was added from 0.1 to 10ppm for the propose of increasing the mechanical property and the surface state. The total thickness of electrodeposited copper foil was decreased with increasing the amount of organic compounds. There was not so much significant effect of the current density. It has been observed that mechanical property and surface luminous intensity increase with increasing concentration of organic compounds.

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역청콘크리트의 성질과 아스팔트 시멘트 크로마토그램과의 상관관계 (Correlation between Property of Bituminous Concrete and Chromatogram of Asphalt Cement Used)

  • 김광우;연규석;박제선
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1990년도 가을 학술발표회 논문집
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    • pp.107-112
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    • 1990
  • Chromatograms of asphalt cements were observed using high pressure - gel permeation chromatography (HP-GPC). The chromatogram characterzed profile of molecular size distribution of asphalt cements. Bituminous concretes using the asphalt cements were prepared in laboratory to measure mechanical properties, tensile strength (TS) and resilient modulus (MR), in dry and wet conditions. Three sources of AC-20 Asphalt cements and one aggregates were used for GPC test and strength test. Results of mechanical property tests and GPC tests were analyzed to evaluate correlation between those two results. Regression analysis showed strong correlation between a mechanical property and sliced percent areas of GPC profile. Mathematical models were developed for estimating mechanical properties of asphalt cement concrete based on HP-GPC data.

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Electro-mechanical Property Evaluation of REBCO Coated Conductor Tape with Stainless Steel Substrate

  • Dedicatoria, M.J.;Shin, H.S.;Ha, H.S.;Oh, S.S.;Moon, S.H.
    • 한국초전도ㆍ저온공학회논문지
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    • 제12권4호
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    • pp.20-23
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    • 2010
  • In this study, the electromechanical property of REBCO coated conductor (CC) tape adopting a stainless steel substrate has been investigated. Sample was subjected to uniaxial tension and measured its mechanical properties at RT and 77 K. $I_c-{\varepsilon}_t$ relations was also studied in which the strain and stress corresponding to the 95% $I_c$ retention and reversible strain limit were measured. In addition, these results were compared to the case of conventional REBCO CC tape adopting a Hastelloy substrate. As a result, by adopting a stainless steel substrate comparable strength and good electromechanical property to Hastelloy one could be achieved.

화학 기계적 연마에 의한 리튬 니오베이트의 광학 특성에 관한 연구 (Study on Optical Properties of Lithium niobate using Chemical Mechanical Polishing)

  • 정석훈;김영진;이현섭;정해도
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.121-122
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    • 2008
  • Lithium Niobate (LN:LiNbO3) is a compound of niobium, lithium and oxygen. The characteristics of LN are piezoelectricity, ferroelectricity and photoelectricity, and which is widely used in surface acoustic wave (SAW). To manufacture LN device, the LN surface should be a smooth surface and defect-free because of optical property, but the LN material is processed difficult by traditional processes such as grinding and mechanical polishing (MP) because of its brittleness. To decrease defects, chemical mechanical polishing (CMP) was applied to the LN wafer. In this study, the suitable parameters scuh as pressure and relative velocity, were investigated for the LN CMP process. To improve roughness, the LN CMP was performed using the parameters that were the highest removal rate among process parameters. And, evaluation of optical property was performed by the optical reflectance and non-linear characteristic.

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Blending Effect on the Mechanical and Hand Properties of Wool/Acrylic Blend Knits

  • Park Myung-Ja
    • The International Journal of Costume Culture
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    • 제8권1호
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    • pp.23-31
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    • 2005
  • Mechanical properties and hand evaluation of wool/acrylic(W/A) blend knits were conducted before and after repeated washing to get the optimum W/A blending ratio, which could help achieve the optimum mechanical and hand properties of the knits. The five test fabrics using the yarns with different W/A blending ratios($\%$), 100/0, 70/30, 50/50, 30/70, 0/100, were knitted. The fabrics were washed by a rotating drum type washing machine. Then, objective mechanical and hand properties were evaluated by KES-FB, Kawabata evalution system for fabric. The results are as follows: there was no change in the hand value of the knitted fabric with the W/A-blended yarn caused by the change in the blending ratio before washing. After washing, however, the increase of acrylic's blending rate caused the bending property to decrease proportionally, while the friction coefficient of the surface property increased. Furthermore, the study showed that W/A 50/50 possesses the most superior tensile property and shearing property, which could attain the optimum blending ratio. Similar results in hand value were derived in all the samples. After washing, however, the increase in acrylic's blending rate caused a proportional decrease in KOSHI and an increase in FUKURAMI. In addition, W/A 50/50 gained the biggest NUMERI value, again corresponding to the optimum blending ratio. Similar results in total hand value were derived in all the samples before washing. After washing, though, all the total hand values decreased, and, as the wool fabric's blending rate increased, the total hand values proportionally decreased further.

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니켈 도금층의 기계적 성질에 미치는 전해조건의 영향 (Effect of Electrolysis Condition on Mechanical Property of Ni Electrodeposits)

  • 강수영;이정자;양승기;황운석
    • 한국표면공학회지
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    • 제48권2호
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    • pp.62-67
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    • 2015
  • Nickel is a commercially important and versatile element in electroplating. The applications of nickel electroplating fall into three main categories: decorative, functional and electroforming. In decorative applications, electroplated nickel is most often applied in combination with electrodeposited chromium. Nickel is deposited on surfaces to improve corrosion and wear resistance or modify magnetic and other properties. Electroforming is electroplating applied to the fabrication of products of various kinds. Nickel is deposited onto a substrate and then removed from it to create a part made entirely of nickel. In this study, mechanical property of Ni electrodeposits in various manufacturing condition such as temperature, current density, pH and electrolyte content, was investigated to understand effect of electrolysis condition on mechanical property. Vickers hardness increased as the temperature and pH increased and current density and electrolyte content decreased and pH increased. The results were explained by cathode overvoltage and hydrogen evolution.

나노인덴테이션을 이용한 MLCC용 BaTiO3 세라믹스의 기계적 물성평가 (Feasibility Test for Mechanical Property Characterization of BaTiO3 Ceramics for MLCC Application Using Nanoindentation)

  • 류성수;김성원;김형준;김형태
    • 한국분말재료학회지
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    • 제16권1호
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    • pp.37-42
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    • 2009
  • In this study, the feasible test for the mechanical property characterization of $BaTiO_3$ ceramics and multi-layer ceramic capacitor(MLCC) was performed with nanoindentation technique. In case of $BaTiO_3$ ceramics, hardness and elastic modulus are dependent on the densification of specimen showing the highest hardness and elastic modulus values of 12.3 GPa and 155 GPa, respectively at $1260^{\circ}C$. In case of MLCC chip, hardness of dielectric layer was lower than that of margin region. The nanoindentation method could be useful tool for the measurement of mechanical property within $BaTiO_3$ dielectric layer of very thin thickness in high capacitance MLCC.