• Journal of the Korean Ceramic Society
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• v.15 no.2
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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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• v.8 no.2
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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.

• Particle and aerosol research
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• v.8 no.2
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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.

• Journal of the Korean Ceramic Society
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• v.26 no.3
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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.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.4
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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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• v.30 no.3
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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.

• Journal of the Korea Concrete Institute
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• v.13 no.3
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• pp.221-227
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• 2001

Both strength and stiffness of RC structures strengthened by a steel plate greatly increase and however, their ductility might not be sufficient because premature failures usually occur at the adhesive-concrete interface. In this study, Mohr-Coulomb criterion was adopted to examine the bonding failure mechanism, and the diagonal shear bonding test, the direct shear bonding test, and the flexural test on RC beams strengthened by a steel plate were carried out to measure the bonding properties. It is found from the experimental and numerical results that the cohesive strengths of epoxy-concrete interfaces are ranging from 50 kgf/㎠ to 70 kgf/㎠ when the friction angle is 45°. Bonding failure loads can be predicted by applying the bonding properties to the structural analysis of RC beams strengthened by steel plate. By considering them in the design of strengthened beams, the premature failure would be effectively prevented.

• Journal of Distribution Research
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• v.13 no.2
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• pp.29-57
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• 2008

Empirical model was developed to test the building mechanism of trust dimensions and loyalty with the suppliers' bonding tactics to service firms. And interactive effects between suppliers' bonding tactics and service firms' store age was hypothesized in the trust-loyalty building processes. The model was tested in the context of animal clinics which belong to Korean Animal Hospital Association (KAHA). The data was analysed using structural equation model (SEM). The findings are as follows. First, two different relational bonding tactics play different roles in their effects on building trust dimensions toward suppliers. While supplier's social bonding tactic significantly influences on both the affective and cognitive trust of service firms, suppliers' structural bonding tactic only influences significantly on affective trust of service firms. Second, while suppliers' social bonding tactic influences on building service firms' loyalty significantly, suppliers' structural bonding tactic doesn't influence on building their loyalty. Suppliers' structural bonding tactic influences on building their loyalty indirectly through affective trust. Third, while service firms' affective trust influences on building loyalty significantly, cognitive trust doesn't. Their cognitive trust influences on building loyalty indirectly through affective trust. Fourth, the higher the firms' store age is, the more suppliers use social bonding tactics to build trust and loyalty directly. While the shorter the firms' store age is, the more suppliers partially use both the social and structural bonding tactics to build trust and loyalty. In conclusion, in the context of animal clinics' distribution channels, suppliers' relational bonding tactics with service firms differently influence to build trust sub-dimensions and loyalty. And, suppliers should take note of the interactive role of service firms' store age in the utilization of the different bonding tactics to build service firms' trust and loyalty toward suppliers. At the end of the paper, managerial implications, limitations, and future research directions are suggested.

• Korean Journal of Metals and Materials
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• v.47 no.1
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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.

• Journal of Korea Multimedia Society
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• v.18 no.9
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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.