• Title/Summary/Keyword: Surface characteristic

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Analysis of the Surface Characterisitics of Microstickies by Contact Angle Measurement (접촉각 측정을 통한 스틱키의 표면화학적 특성 분석)

  • Park, Il;Lee. Hak-Lae
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.37 no.2 s.110
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    • pp.21-29
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    • 2005
  • Increase in the utilization rate of recycled paper has significantly increased the problem associated with stickies. Despite the effort to eliminate contaminants from recycled furnishes, stickies are still the most serious obstacle in using recycled paper. The amount of micro stickies that are too small to be eliminated by screening, tends to increase significantly as the closure level of white water system is increased and the quality of raw material deteriorates. To establish a process efficient in removing micro stickies is strongly required. In this study, the surface characteristic of micro stickies was investigated with contact angle measurement. Surface energies of MCC, PSA film and model micro stickies were 53.37 mN/m, 29.75mN/m, and 29.63mN/m, respectively. This indicates that the surface characteristic of MMS is very similar to PSA. Thus, solvent coating of PSA and evaporation of the solvent provided excellent model micro stickies for flotation experiment.

A Study on the Surface Grinding Characteristic of Engineering Cramics (엔지니어링 세라믹스의 평면 연삭 가공 특성에 관한 연구)

  • Kang, J.H.;Heo, S.J.;Kim, W.L.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.2 no.6
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    • pp.38-49
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    • 1994
  • In this study, grindability of some representative engineering ceramics are experimentally investigated using resin bond diamond wheel with conventional surface grinding machine, and proper grinding conditions which can be obtained from various experimental results are established also for mechanical components which are proper to domestic circumstances with high reliability. And through the results of experiment, it is confirmed that grinding energies of the ceramics, especially in the case of $Al_2O_3$, are lower than steel with same machining condition in the conventional grinding because of their fine-brittle fracture mode type removal process, though the ceramics are well-known to unmachinable materials. And moreover, the total pass numbers needed for spark-out process to be completed are depend on their mechanical properties because that grinding stiffness is different from each other. The grinding force, ginding power and ground surface roughness are also measured and compared. Furthermore, the experiments carried out in this study, some useful results are obtained with can guide to grind engineering ceramics with conventional surface grinding machine.

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Surface Properties of Artificial Suedes (인조 스웨이드의 표면특성)

  • Roh, Eui Kyung;Oh, Kyung Wha
    • Fashion & Textile Research Journal
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    • v.15 no.2
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    • pp.309-315
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    • 2013
  • This study examines the difference of surface properties according to napping characteristic of artificial suedes, measuring surface structure observation, the contact/non-contact method roughness, warm-cool feeling of touch, and subjective hand evaluation. Surface and cross-section observations showed a discernible difference in fineness, curl, length, mount of napping, and covering power of base fabric. The surface properties of artificial suede evaluated by KES-FB4 showed that the shorter napping length the more smooth surface and the roughness increased reciprocally with friction resistance and surface contour when the nap length reaches a high level. The surface roughness measuring system applied a laser displacement sensor by a non-contact method to assess napping characteristic and the base fabric and napping height. Surface roughness decreased when napping was uniformly covered with base fabric; however, the surface roughness increased specifically with the uneven covering power of the base fabric. For qmax of the suedes, those that had short and smaller amounts of napping increased; however, the napping of length and amount at some stage generated a low qmax value. The warm sensation in all suedes were strongly perceived, but the cool sensation of the perception was lower in the subjective evaluation. Smoothness and softness were perceived when the suede has a long and large amount napping; however, smoothness and hardness were perceived when the suede was short and with the uneven covering power.

3D Elastic Contact Analysis of Sharkskin Surface Pattern (상어 표피 형상의 3차원 탄성접촉해석)

  • Kim, Tae Wan
    • Tribology and Lubricants
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    • v.28 no.6
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    • pp.297-302
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    • 2012
  • We conducted 3D elastic contact analysis of a sharkskin surface pattern for the characteristic assessment of biomimetic shark skin structure pattern for engineering applications. Rough sharkskin surfaces of similar size with real shark skin scales are generated numerically. Under the assumption of the contact of a plate on the generated sharkskin surface, contact performances such as contact pressure, real contact area, and surface separation are evaluated.

A Study on the Precision Machining Characteristics in Heavy Cutting of Al-alloy (Al합금의 중절삭시 정밀가공 특성에 관한 연구)

  • 권용기;김동현
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.10a
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    • pp.203-208
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    • 2002
  • This paper deals with turning experiments of aluminium alloy using a single crystal diamond with round cutting edge. A face cutting was conducted using a special precision machine to study the characteristic phenomena in heavy cutting of aluminium alloy. In many cases, one of the most important matter on the surface integrity is about a damaged layer remaining just under the surface after machining. A machined surface roughness can be improved at a small geometrical surface roughness under special cutting conditions, even if a steady vibration exists between a tool and a workpiece.

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