• 한국세라믹학회지
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• 제15권2호
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• pp.89-97
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• 1978

The basic mechanism of adherence in sintered high purity alumina ceramic-to-metal bonding was studied. Emphasis was placed on flux composition, porosity of the fired ceramics, and metallizing mixtures. The study was conducted on 95 and 99.5% alumina, using molydbenum-manganese, molybdenum-manganese-silicon dioxide metallizing compositions. Metallizing was performed in wet hydrogen (dew point, ＋17$^{\circ}C$) at 145$0^{\circ}C$ for 45min. This experiment indicated that adhernece mechanism of ultra high purity alumina ceramic was attributed to formation of $MnAl_2O_$4, and in the case of 95% alumina containing glass, the migration of glass from the interface into the void of the metal coating was the main role to the adhrence. It showed also that greater the bond-strength was resulted as porosity was increased.

• Journal of Welding and Joining
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• 제8권2호
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• pp.70-79
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• 1990

Stainless clad steels were made through hot rolling process. Backing plates employed in this study were HSLA steel and mild steel. The shear bond strength increased with an increase of the soaking temperature and time. It was also found that the shear bond strength increased with an increase of the reduction ratio. The threshold deformation was observed to be 20% and 10% respectively when the soaking conditions of 15 min. at 900.deg. C and 30 min. at 1000.deg. C were applied. Either the rolling or the transverse direction did not give any significant difference in the shear bond strength. Stainless steel-HSLA steel was superior to stainless steel-mild steel in the same range of magnitude. Because the above experimental results were in contrary to the existing mechanisms, the new model was proposed to describe the bonding mechanism and the void formation.

• 한국입자에어로졸학회지
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• 제8권2호
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• pp.75-81
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• 2012

The strength of lumped cokes can be represented by some index numbers. Although some indexes are suggested, these indexes are not enough to enlighten fracture mechanism. To find essential mechanism, a computational way, discrete element method, is applied to the uniaxial compression test for cylindrical specimen. The cylindrical specimen is a kind of lumped particle mass with parallel bonding that will be broken when the normal stress and shear stress is over a critical value. It is revealed that the primary factors for cokes fracture are parallel spring constant, parallel bond strength, bonding radius and packing ratio the parallel bond strength and radius of the parallel combination the packing density. Especially, parallel spring constant is directly related with elastic constant and yield strength.

• 한국세라믹학회지
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• 제26권3호
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• pp.371-380
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• 1989

The purpose of this experiment is to elucidate the reaction mechanism concerning to the formation of crystalline BaTiO3 synthesized by adding the pH control agent(KOH soln) in TiCl4 and BaCl2 solution (Wet direct synthetic method). In this expeirment, it is identified that the amorphous barium-titanate having Ba-O-Ti bonding is formed above pH5 due to the -OH- ion and Ti-gel is formed below pH5 due to the polymerization of metatitanic acid. The bonding of the amorphous Ba-O-Ti is identified by FT-IR spectrum and crystallization temperature is about 82$0^{\circ}C$. If the pH of the above system according to the -OH- ion concentration is above 13.8, the polymerized metatitanic acid will be depolymerized and produce [TiO3]2+ion and crystalline BaTiO3 is formed by reacting the produced [TiO3]-- ion with the active Ba++ ion.

• 마이크로전자및패키징학회지
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• 제23권4호
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• pp.69-77
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• 2016

We propose nano-scale Cu direct bonding technology using ultra-high density Cu nano-pillar (CNP) with for high stacking yield exascale 2.5D/3D integration. We clarified the joining mechanism of nano-scale Cu direct bonding using CNP. Nano-scale Cu pillar easily bond with Cu electrode by re-crystallization of CNP due to the solid phase diffusion and by morphology change of CNP to minimize interfacial energy at relatively lower temperature and pressure compared to conventional micro-scale Cu direct bonding. We confirmed for the first time that 4.3 million electrodes per die are successfully connected in series with the joining yield of 100%. The joining resistance of CNP bundle with $80{\mu}m$ height is around 30 m for each pair of $10{\mu}m$ dia. electrode. Capacitance value of CNP bundle with $3{\mu}m$ length and $80{\mu}m$ height is around 0.6fF. Eye-diagram pattern shows no degradation even at 10Gbps data rate after the lamination of anisotropic conductive film.

• Journal of Welding and Joining
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• 제30권3호
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• pp.38-43
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• 2012

In this study, active metal brazing methods for $ZrO_2$ and Ti alloy were discussed. To get a successful metal-ceramic bonding, various factors (melting temperature, corrosion, sag resistance, thermal expansion coefficient etc. of base materilas and filler metal) should be considered. Moreover, in order to clarify bonding between the metal and ceramic, the mechanism of the interfacial structure of the joints should be identified. The driving force for the formation of metal and ceramic interfaces is the reduction of the free energy which occurs when their contact becomes complete. Interfacial bonding depends on the material combinations and the bonding processes. This study describes the bonding between ceramic and metal in an active metal brazing.

• 콘크리트학회논문집
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• 제13권3호
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• pp.221-227
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• 2001

강판으로 철근콘크리트 보를 휨보강하면 보의 강성과 강도는 현저하게 증가하나 부착면에서의 조기파괴로 인하여 충분한 연성을 발휘하지 못하는 경우가 자주 발생한다. 본 연구에서는 에폭시와 콘크리트 계면에서의 부착파괴 메카니즘을 규명하기 위하여 Mohr-Coulomb 규준을 채택하였으며, 에폭시-콘크리트 계면의 부착특성을 결정하기 위하여 사전단 부착실험, 직접전단 부착실험 및 휨보강 부재실험을 수행하였다. 실험과 수치해석을 통하여 에폭시-콘크리트 계면의 내부마찰각이 45$^{\circ}$ 일 때 점착력은 50 kgf/$\textrm{cm}^2$~70 kgf/$\textrm{cm}^2$을 얻었으며, 이를 강판으로 보강된 RC보의 구조계산에 적용하여 파괴하중을 예측함으로써 보강보의 조기파괴를 효과적으로 방지할 수 있을 것으로 판단된다.

• 한국유통학회지:유통연구
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• 제13권2호
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• pp.29-57
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• 2008

본 연구는 유통경로 상에서 서비스기업의 공급업체에 대한 신뢰 및 충성도 구축과정에서 공급업체의 유대관계전략과 서비스기업의 점포 운영기간 사이에 상호작용효과를 실증적으로 분석하였다. 실증을 위해 한국동물병원협회 소속의 214개 동물병원을 표본으로 하여 설문을 수집한 후, 구조방정식 모델을 활용하여 가설을 검증하였다. 실증분석의 결과는 다음과 같다. 첫째, 유통경로 구성원인 공급업체의 서비스기업에 대한 유대관계 전략에 따라 서비스기업이 구축하고자하는 신뢰의 유형에 대해 서로 다른 영향을 주는 것을 확인하였다. 즉, 공급업체의 사회적 유대전략은 서비스기업의 두 가지 유형의 감정적 신뢰 및 인지적 신뢰구축에 모두 영향을 주지만, 구조적 유대전략은 서비스기업의 감정적 신뢰에 영향을 주지만 인지적 신뢰에는 영향을 주지 않았다. 둘째, 공급업체의 사회적 유대전략은 서비스기업의 공급업체에 대한 충성도 구축에 직접적인 영향을 미치지만, 구조적 유대는 충성도 구축에 직접적으로 영향을 미치지 않고 감정적인 신뢰를 통하여 영향을 미쳤다. 셋째, 서비스기업의 감정적 신뢰는 그들의 공급업체에 대한 충성도 구축에 직접적인 영향을 주지만, 서비스기업의 인지적 신뢰는 공급업체에 대한 충성도 구축에 직접적인 영향을 주지 않고 감정적 신뢰를 통하여 형성되었다. 넷째, 서비스기업의 점포 운영기간이 길수록 공급업체는 사회적 유대를 활용하여 서비스기업의 신뢰 및 충성도를 직접적으로 구축하나, 점포 운영기간이 짧을수록 사회적 유대 및 구조적 유대를 부분적으로 활용하여 신뢰를 먼저 구축하고 그런 다음 충성도를 간접적으로 구축하였다. 따라서 유통경로 구성원들 사이에 서비스기업이 그들의 사업파트너인 공급업체에 대한 신뢰의 유형 및 충성도를 구축하기 위해서 서로 다른 유대관계 전략을 활용하며, 공급업체는 서비스 기업의 점포 운영기간에 따라 공급업체에 대한 서비스기업의 신뢰 및 충성도를 구축하는 과정에서 해당점포의 운영기간에 대한 상호작용효과를 고려할 필요가 있다. 마지막으로 연구의 시사점, 한계점 그리고 향후 연구방향에 대해 논의하였다.

• 대한금속재료학회지
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• 제47권1호
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• pp.26-31
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• 2009

The effects of $Ar/O_2$ ion-beam pre-treatment conditions on the interfacial adhesion energy of sputterdeposited Cu thin film to FR-4 substrate were systematically investigated in order to understand the interfacial bonding mechanism for practical application to advanced chip-in-substrate package systems. Measured peel strength increases from $45.8{\pm}5.7g/mm$ to $61.3{\pm}2.4g/mm$ by $Ar/O_2$ ion-beam pre-treatment with anode voltage of 64 V. Interfacial bonding mechanism between sputter-deposited Cu film and FR-4 substrate seems to be dominated by chemical bonding effect rather than mechanical interlocking effect. It is found that chemical bonding intensity between carbon and oxygen at FR-4 surface increases due to $Ar/O_2$ ion-beam pretreatment, which seems to be related to the strong adhesion energy between sputter-deposited Cu film and FR-4 substrate.

• 한국멀티미디어학회논문지
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• 제18권9호
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• pp.1118-1130
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• 2015

The current study explores a possible mechanism through which game users' integrated sociopsychological factors lead to a higher level of life satisfaction, based on desire-fulfillment theory as well as hedonic and eudaimonic approaches to happiness. Using data from a survey of 789 game users in South Korea, we tested the relationships of psychological variables (self-esteem and game and life-efficacy), social variables (bonding and bridging social capital), and demographic variables (age and gender) with life satisfaction. Results show that self-esteem and game efficacy were an important antecedent to the degree of users' life satisfaction. Both bonding and bridging social capital increased life satisfaction. The importance of perspectives as well as their implications for game users and further associated research is explored.