• 한국군사과학기술학회지
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• 제7권2호
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• pp.100-108
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• 2004

Nitramine-polymer composites suffer from a problem known as dewetting. Dewetting adversely affects the performance and the sensitivity characteristics of an explosive composition. Voids, which are generated between explosive particles and binder on dewetting, act as initiation sites. For a PBXs as well as propellants, where good adhesion and mechanical properties are of great importance, dewetting therefore must be prevented by strong adhesion between the filler and the binder. The surface energy of materials is measured by Wilhelmy plate and wicking method. The interfacial energy between the filler and the binder is calculated from the disperse phase and the polar phase of surface energy. Time dependent compressive properties of composite explosives have been determined by stress-strain curves obtained at different strain rates and temperatures. The interfacial state of the PBX was observed through SEM. It was found from the result that the interface between the explosive and the binder becomes better adhesion with decreasing interfacial tension and increasing work of adhesion. The result clearly shows that the castable PBX has good adhesion more than the pressable PBX.

• 정보저장시스템학회논문집
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• 제2권2호
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• pp.105-110
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• 2006

Study for toner adhesion is 3non as an important role in electrophotography. In this research, a centrifugal detachment method was used to measure the adhesion force of several hundred particles simultaneously and to determine its sensitivity to particle size. For uncharged toner particles, we estimated the van der Waals force based on the centrifugal force experiments. Then for charged toner particles, the centrifugal force experiments were carried out. The difference between the results for charged toner particles and the results for uncharged toner particles was compared with the image force calculated from a model which assumed that the toner charge was located at the center of the particle. In the calculations, experimental data obtained by E-SPART (Electrical-Single Particle Aerodynamic Relaxation Time) analyzer were used. The adhesion force of micro-sized toner particles deposited on the DR surface was found to be approximately $1{\sim}3$ nN.

• 한국추진공학회지
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• 제24권5호
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• pp.84-90
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• 2020

본 논문은 이종추진제(1차 추진제/2차 추진제) 접착에 필요한 코팅제에 대해 기술하였다. 코팅제는 유기용매, 고분자 경화제, 경화촉매로 구성되어 있다. 경화촉매인 FeAA를 0.14 wt% 이상 적용한 코팅제는 2차 추진제 경화 직후 시험한 결과 접착계면이 아닌 추진제가 파단되는 결과를 확인하였으며, 0.10 wt% 이하에서는 접착계면이 파단되었다. 경화촉매는 2차 추진제 경화 직후 접착계면이 파단되는 결과를 확인하였다. 또한 TPB 경화촉매를 적용한 코팅제의 경우 시간이 경과함에 따라 1차 추진제와 2차 추진제간의 접착력이 증가하는 결과를 확인하였다.

• 한국재료학회지
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• 제20권6호
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• pp.319-325
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• 2010

3-D IC integration enables the smallest form factor and highest performance due to the shortest and most plentiful interconnects between chips. Direct metal bonding has several advantages over the solder-based bonding, including lower electrical resistivity, better electromigration resistance and more reduced interconnect RC delay, while high process temperature is one of the major bottlenecks of metal direct bonding because it can negatively influence device reliability and manufacturing yield. We performed quantitative analyses of the interfacial properties of Al-Al bonds with varying process parameters, bonding temperature, bonding time, and bonding environment. A 4-point bending method was used to measure the interfacial adhesion energy. The quantitative interfacial adhesion energy measured by a 4-point bending test shows 1.33, 2.25, and $6.44\;J/m^2$ for 400, 450, and $500^{\circ}C$, respectively, in a $N_2$ atmosphere. Increasing the bonding time from 1 to 4 hrs enhanced the interfacial fracture toughness while the effects of forming gas were negligible, which were correlated to the bonding interface analysis results. XPS depth analysis results on the delaminated interfaces showed that the relative area fraction of aluminum oxide to the pure aluminum phase near the bonding surfaces match well the variations of interfacial adhesion energies with bonding process conditions.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 추계학술발표대회
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• pp.18.1-18.1
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• 2011

Some applications of carbon nanotubes (CNTs) as field emitters, such as x-ray tubes and microwave amplifiers, require high current emission from a small emitter area. To emit the high current density, CNT emitters should be optimally fabricated in terms of material properties and morphological aspects including high crystallinity, aspect ratio, distribution density, height uniformity, adhesion on a substrate, low outgassing rate during electron emission in vacuum, etc. In particular, adhesion of emitters on the substrate is one of the most important parameters to be secured for high current field emission from CNTs. So, we attempted a novel approach to improve the adhesion of CNT emitters by incorporating metal oxide layers between CNT emitters. In our previous study, CNT emitters were fabricated on a metal mesh by filtrating the aqueous suspensions containing both highly crystalline thin multiwalled CNTs and thick entangled multiwalled CNTs. However, the adhesion of CNT film was not enough to produce a high emission current for an extended period of time even after adopting the metal mesh as a fixing substrate of the CNT film. While a high current was emitted, some part of the film was shown to delaminate. In order to strengthen the CNT networks, cobalt-nickel oxides were incorporated into the film. After coating the oxide layer, the CNT tips seemed to be more strongly adhered on the CNT bush. Without the oxide layer, the field emission voltage-current curve moved fast to a high voltage side as increasing the number of voltage sweeps. With the cobalt-nickel oxide incorporated, however, the curve does not move after the second voltage sweep. Such improvement of emission properties seemed to be attributed to stronger adhesion of the CNT film which was imparted by the cobalt-nickel oxide layer between CNT networks. Observed after field emission for an extended period of time, the CNT film with the oxide layer showed less damage on the surface caused by high current emission.

• 접착 및 계면
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• 제8권3호
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• pp.1-8
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• 2007

폴리우레탄 폼 소재에 평판형 플라즈마 전처리 방식을 적용시켜 접촉각 및 접착력을 향상시켰다. 플라즈마 반응기의 최적의 반응조건을 조사하기 위해서 반응가스(질소, 아르곤, 산소, 공기), 가스의 유량(30~150 mL/min), 그리고 반응시간(0~30초) 등을 변화시켜 전처리하여 진공식 플라즈마 방식과 비교 검토하였다. 처리 후 소재의 표면 변화는 SEM과 ATR-FTIR을 이용하여 측정하였다. 폴리우레탄 폼에서 질소의 유량이 100 mL/min이고 반응시간이 10초일 때 접촉각의 저하에 따른 가장 좋은 접착력의 결과를 보여 주었다. 결과적으로 평판형 플라즈마 조작 방식에 의한 처리로 폴리우레탄 폼의 접촉각과 접착박리강도가 개선되었음을 확인하였다.

• 소성∙가공
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• 제15권5호
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• pp.366-372
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• 2006

The effect of coating time in arc ion plating on surface properties of the TiN-coated high speed steel(SKH51) is presented in this paper. Surface roughness, micro-hardness, coated thickness, atomic distribution of TiN and adhesion strength are measured for various coating times. It has been shown that the coating time has a deep influence on the micro-hardness, the coated thickness, the atomic distribution of Ti and the adhesion strength of the SKH51 steels but that it has little influence on the surface roughness.

• 한국기계가공학회지
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• 제10권5호
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• pp.44-50
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• 2011

The effect of deposition time in arc ion plating on surface properties of the TiN-coated SM45C steel is presented in this paper. The surface roughness, micro-particle, micro-hardness, coated thickness, atomic distribution of TiN, and adhesion strength are measured for various deposition times. It has been shown that the deposition time has a considerable effect on the micro-hardness, the coated thickness, and the atomic distribution of TiN of the SM45C steels but that it has little influence on the surface roughness and adhesion strength.

• Korean Chemical Engineering Research
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• 제48권5호
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• pp.556-560
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• 2010

부타디엔 고무 소재의 접착력을 향상시키기 위하여 대기압 표면개질방식을 적용시켰다. 평판형 플라즈마반응기의 최적의 반응조건을 구하기 위하여 반응기체(질소, 아르곤, 산소, 공기), 기체유량(30~100 mL/min), 플라즈마 처리시간(0~30초) 및 선처리제의 개질방법(GMA, 2-HEMA)을 변화시켜 실험하였다. 처리 전후의 소재의 표면변화는 SEM과 ATR-FTIR로 측정하였다. 기체의 유량과 처리시간이 증가함에 따라 접촉각이 감소하였고, 반응 기체는 공기로 유량 60 mL/min, 처리시간 5초 및 2-HEMA 첨가 선처리제를 사용하였을 때 최대의 접착박리강도를 나타내었다. 결과적으로 대기압식 평판형 플라즈마 처리방식으로 고무소재 표면의 젖음성과 접착박리강도가 개선되었음을 확인하였다.

• 접착 및 계면
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• 제17권1호
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• pp.21-28
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• 2016

본 연구에서는 불법 조업 어선 제압 및 장비 불용화를 위한 접착형 퇴치제 개발의 일환으로 발포형 생분해성 폴리우레탄 연구를 수행하였다. 발포형 폴리우레탄 접착제는 폴리에스터계 및 폴리에테르 폴리올을 포함하는 주재와 고분자형의 이소시아네이트로 이루어진 경화제를 혼합하여 반응이 완결되는 2액형으로, 단기간의 생분해성을 위해 주재에 starch와 dextrin 및 amylase 등을 첨가하여 4주간 약 34%의 생분해도를 OECD 301C법에 의해 얻을 수 있었다. 주재와 경화제의 온도에 따른 점도를 $0{\sim}50^{\circ}C$의 온도범위에서 측정하여 혼합 시 참고할 수 있도록 하였으며, 또한 신속한 발포 및 접착성능을 위해서 $0{\sim}50^{\circ}C$의 온도 범위에서 발포형 폴리우레탄 접착제의 반응 완결 속도(rising time)를 조절하여 1 min 내외로 제어하였다. 또한 면 직물에 대한 T-peel 시험을 수행한 결과 최대 20.78 N/cm, 평균 11.95 N/cm의 접착력을 얻을 수 있었다.