• 한국의학물리학회지:의학물리
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• 제26권4호
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• pp.273-279
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• 2015

최근에는 스마트 헬스 의료기기의 발전과 보급이 늘어나면서 빈번한 사용에 대한 내구성과 내열성 및 환경과 외장의 수려함이 요구되고 있다. 이에 상응하는 조건과 외장의 펄감을 표현하는 스마트 헬스 의료기기용 고기능 전착기술에 대한 산업적 수요가 크게 늘어나고 있다. 전착도장으로 펄감을 가지는 도막을 형성하기 위해서는 일반적으로 전착도료에 펄 분말을 첨가하여 도장하지만, 펄 분말을 사용하지 않고 미려한 펄감을 표현할 수 있는 새로운 방식의 펄감을 표현하는 전착도장방법으로 스마트 헬스 의료기기용 고기능 전착 기술을 연구하였다. 본 연구에서는 가장 적합한 Texture형성을 찾고, Dilution Recipe를 구하기 위해 안료(Pigment)인 ED-600과 ED-600S, ED-MX, ED-M를 이용한 실험에서 안료들의 조성물 배합비를 찾기 위해 각 안료들의 여러 농도로 실험하여 가장 적합한 조건을 찾고자 하였다. 실험 결과 ED-600과 ED-MX (15% 고형분)의 적합한 농도에서 가장 정착이 우수함을 확인할 수 있었고, 정착 시료를 여러 온도($20{\sim}40^{\circ}C$) 조건에서 수세 후 검사 및 테스트하여, 건조 과정의 실험 결과 $180{\pm}10^{\circ}C$와 $30{\pm}5min$ 건조 조건에서 가장 좋은 결과를 나타냄을 알 수 있었다. 연구 결과로 지금껏 펄 분말을 첨가하여 미려한 펄감을 표현하는 스마트 헬스 의료기기용 고기능 전착방법을 전착도료에 펄 분말을 첨가하지 않고도 피도물의 표면에서 자연물에 의한 표현같은 느낌을 주는 감성품질을 나타내는 새로운 방식의 펄감을 표현하는 전착도장 기술을 얻게 되었으며, 아울러 제품의 경도 및 내열성과 내식성 등을 만족한 제품과 가격 경쟁력을 확보할 수 있을 것으로 추정된다.

• 한국표면공학회지
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• 제47권3호
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• pp.137-146
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• 2014

The important drawback of epoxy electrodeposition(ED) coatings is the lack of the weathering resistance caused by the structure of bisphenol A. To improve this yellowing phenomena, acryl ED coatings have been developed. Compared with the epoxy ED coatings, however, acryl ED coatings are relatively weak in the corrosion resistance and mechanical properties. The purpose of this study is complemented their drawbacks by mixing epoxy and acryl ED paints. The salt spray, accelerated weathering test(QUV) and cupping, bending, impact test were employed to investigate the corrosion resistance, weathering resistance, and mechanical properties of ED coatings. When the ratio of acryl to epoxy resin of ED coating is 0.33, the weathering resistances are appropriately improved in condition maintaining the corrosion resistance. It was shown that the weathering resistance for epoxy ED coating was adjusted by optimally mixing acryl ED paint.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 추계학술발표대회 논문집
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• pp.153-157
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• 2001

Interfacial properties and microfailure modes of electrodeposition (ED) treated carbon fiber reinforced polyetherimide (PEI) toughened epoxy composite were investigated using microdroplet test and the measurement of surface wettability. As PEI content increased, Interfacial shear strength (IFSS) increased due to enhanced toughness and plastic deformation of PEI. In the untreated case, IFSS increased with adding PEI content, and IFSS of pure PEI matrix showed the highest. On the other hand, for ED-treated case IFSS increased with PEI content with rather low improvement rate. The work of adhesion between fiber and matrix was not directly proportional to IFSS for both the untreated and ED-treated cases. The matrix toughness might contribute to IFSS more likely than the surface wettability. Interfacial properties of epoxy-PEI composite can be affected efficiently by both the control of matrix toughness and ED treatment.

• Macromolecular Research
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• 제10권1호
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• pp.24-33
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• 2002

Interfacial and microfailure properties of carbon fiber/epoxy composites were evaluated using both tensile fragmentation and compressive Broutman tests. A monomeric and two polymeric coupling agents were applied via the electrodeposition (ED) and the dipping applications. A monomeric and a polymeric coupling agent showed significant and comparable improvements in interfacial shear strength (IFSS) compared to the untreated case under both tensile and compressive tests. Typical microfailure modes including cone-shaped fiber break, matrix cracking, and partial interlayer failure were observed under tension, whereas the diagonal slipped failure at both ends of the fractured fiber appeared under compression. Adsorption and shear displacement mechanisms at the interface were described in terms of electrical attraction and primary and secondary bonding forces.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 추계학술발표대회 논문집
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• pp.116-120
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• 2001

Fiber fracture is one of the dominant failure phenomena to determine total mechanical properties in composites. Fiber fracture locations were measured by optical microscopic method and acoustic emission (AE) as functions of matrix toughness and surface treatment by the electrodeposition (ED), and then two methods were compared. Two AE sensors were attached on the epoxy specimen and fiber fracture signals were detected with elapsed time. The interfacial shear stress (IFSS) was measured using tensile fragmentation test and AE system. In ED-treated case, the number of the fiber fracture measured by an optical method and AE was more than that of the untreated case. The signal number measured by AE were rather smaller than the number of fragments measured by optical method, since some fiber fracture signals were lost while AE detection. However, one-to-one correspondence between the x-position location by AE and real break positions by optical method was generally established well. The fiber break source location using AE can be a valuable method to measure IFSS for semi- or nontransparent matrix composites nondestructively (NDT).

• Macromolecular Research
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• 제8권4호
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• pp.153-164
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• 2000

By electrodeposition (ED) using a monomeric- and two polymeric coupling agents, the interfacial shear strength (IFSS) of carbon fiber/epoxy composites was investigated by fragmentation test. ED results were compared with the dipping and the untreated cases under dry and wet conditions. Multi-fiber composites (MFC) were used for the direct comparison for the untreated and the treated cases. Various treating conditions including time, concentration and temperature were evaluated, respectively. Under dry and wet conditions ED treatment exhibited much higher IFSS improvement compared to the dipping and the untreated cases. Monomeric- and polymeric coupling agents exhibited the comparative IFSS improvement. Adsorption mechanism between coupling agents and carbon fiber was analyzed in terms of the electrolyte molecular interactions during ED process based on to the chain mobility. The microfailure modes occurring from the fiber break, matrix and interlayer cracks were correlated to IFSS.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 추계학술발표대회 논문집
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• pp.17-21
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• 2000

Logarithmic electrical resistivity of the untreated or thin diameter carbon fiber composite increased suddenly to the infinity when the fiber fracture occurred by tensile electro-micromechanical test, whereas that of the ED or thick fiber composite increased relatively broadly up to the infinity. Electrical resistance of single-carbon fiber composite increased suddenly due to electrical disconnection by the fiber fracture in tensile electro-micromechanical test, whereas that of SFC increased stepwise due to the occurrence of the partial electrical contact with increasing the buckling or overlapping in compressive test. Electrical resistivity measurement can be very useful technique to evaluate interfacial properties and to monitor curing behavior of single-carbon fiber/epoxy composite under tensile/compressive loading.

• Composites Research
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• 제15권3호
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• pp.39-44
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• 2002

Micromechanical 시험법을 이용하여 전기증착된 탄소섬유와 polyetherimide (PEI)로 강인화된 에폭시 기지재료 사이의 계면물성과 미세파괴형상을 연구하였다. 계면전단강도 향상을 위해 전기증착법을 이용하여 탄소섬유를 표면 처리하였다. PEI 함량이 증가함에 따라 소성변형과 파괴인성 증가로 인해 계면전단강도는 점차적으로 증가하는 경향을 보였으며, 미처리의 경우에 순수 PEI의 계면전단강도가 가장 큰 값을 보였다. 반면 전기증착의 경우에 계면전단강도는 PEI를 첨가함에 따라서 증가하였지만 그 증가폭은 미처리의 경우 보다 작았다. 미처리의 경우에서 순수 에폭시는 취성파괴 형상을 보인 반면 순수 PEI는 연성파괴 형상을 보였고 전기증착의 경우 순수 에폭시는 미처리와는 달리 연성파괴 형상을 보임을 관찰할 수 있었다. PEI 첨가에 의한 파괴인성 강화와 전기증착에 의한 화학결함 및 계면층의 존재는 복합재료의 계면물성 향상에 효과적으로 기여하는 것으로 고려된다.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 춘계학술발표대회 논문집
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• pp.159-162
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• 2000

Interfacial and microfailure properties of carbon fiber/epoxy matrix composites were evaluated using both tensile fragmentation and compressive Broutman tests with acoustic emission (AE). Amino-silane and maleic anhydride polymeric coupling agents were used via the dipping and electrodeposition (ED), respectively. Both coupling agents exhibited higher improvements in interfacial shear strength (IFSS) under tensile tests than compressive cases. However, ED treatment showed higher IFSS improvement than dipping case under both tensile and compressive test. The typical microfailure modes including fiber break, matrix cracking, and interlayer failure were observed during tensile test, whereas the diagonal slippage in fiber ends was observed during compressive test. For both the untreated and treated cases AE distributions were separated well under tensile testing. On the other hand, AE distributions were rather closer under compressive tests because of the difference in failure energies between tensile and compressive loading. Under both loading conditions, fiber breaks occurred around just before and after yielding point. Maximum AE voltage fur the waveform of carbon or basalt fiber breakage under tensile tests exhibited much larger than those under compressive tests.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 1999년도 추계학술발표대회 논문집
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• pp.28-31
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• 1999

Carbon fiber/epoxy composites using electrodeposited monomeric and polymeric coupling agents were compared with the dipping and the untreated cases. Treating conditions such as time, concentration and temperature were optimized. Four-fibers embedded micro-composites were prepared for fragmentation test. Interfacial properties of four-fiber composites with different surface treatments were investigated with simultaneous acoustic emission (AE) monitoring. The microfailure mechanisms occurring from fiber break, matrix and interlayer crackings were examined by AE parameters and an optical microscope. It was found that interfacial shear strength (IFSS) of electrodeposited carbon fibers was much higher than the other cases under dry and wet conditions. Well separated and different-shaped AE groups occurs for the untreated and ED treated case, respectively.