• Journal of the Microelectronics and Packaging Society
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• v.7 no.4
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• pp.31-35
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• 2000

The stress state developed in a thin adhesive layer bonded between the semiconductor chip and the leadframe and subjected to a shear loading is investigated. The boundary element method (BEM) is employed to investigate the behavior of interface stresses. Within the context of a linear elastic theory, a stress singularity of type $\gamma^{\lambda=1}$(0<1<1) exists at the point where the interface between one of the rigid adherends and the adhesive layer intersects the free surface. Such singularity might lead to edge crack or delamination.

• Restorative Dentistry and Endodontics
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• v.29 no.1
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• pp.1-12
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• 2004

이 연구는 발거 소구치에서 5급 와동을 형성하여 접착 시스템 및 와동 위치에 따른 상아질에 대한 접착시스템의 미세 인장결합강도의 차이를 비교, 연구하였다. 접착방법은 resin-modified glass ionomer(Gl), compomer(부식여부에 따라 DE 및 DN군으로 분류), 그리고 상아질 접착제인 Single Bond(SB) 및 Cleayfil SE Bond(SE)와 복합레진(Clearfil AP-X)을 사용한 5개의 실험군으로 분류하였다. 소구치 협측 치경부에 wedge형태의 와동을 형성하고 5종의 접착 시스템을 제조자의 지시에 따라 적용, 충전하여 시편을 제작하여 미세인장결합강도를 측정하고, One-way ANOVA / Duncan's test로 통계분석하였다. SEM 검사는 미세인장결합강도의 시편제작과 동일한 방법으로 시편을 제작한 후 관찰하였다. 실험 결과, 상아질 접착제 및 복합레진(SB, SE)의 미세인장결합강도가 GI보다 높게 나타났고(p<0.05), 치은측이 교합측보다 더 낮게 나타났으며, CI, DE, SE에서 유의성 있게 낮게 나타났다(p<0.05). Compomer에서 conditioning 여부(DN, DE)에 따른 변화는 치은측에서만 유의차 있는 것으로 나타났다. SEM 관찰에서, 교합측의 상아세관은 결합 계면과 평행하게 주행하였고, 치은측에서는 결합계면에 수직으로 주행하는 것으로 관찰되었다.

• Journal of Adhesion and Interface
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• v.3 no.2
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• pp.17-29
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• 2002

Interfacial properties and microfailure degradation mechanisms of the bioabsorbable composites for implant materials were investigated using micromechanical technique and measurement of surface wettability. As hydrolysis time increased, the tensile strength, the modulus and the elongation of poly(ester-amide) (PEA) and bioactive glass fibers decreased, whereas those of chitosan fiber almost did not change. Interfacial shear strength (IFSS) between bioactive glass fiber and poly-L-lactide (PLLA) was much higher than PEA or chitosan fiber/PLLA systems using dual matrix composite (DMC) specimen. The decreasing rate of IFSS was the fastest in bioactive glass fiber/PLLA composites whereas that of chitosan fiber/PLLA composites was the slowest. Work of adhesion, $W_a$ between bioactive glass fiber and PLLA was the highest, and the wettability results were consistent with the IFSS. Interfacial properties and microfailure degradation mechanisms can be important factors to control bioabsorbable composite performance.

• Journal of Adhesion and Interface
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• v.8 no.3
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• pp.9-15
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• 2007

The interfacial evaluation of surface modified Jute fiber/polypropylene (PP) composites before and after hydration was investigated using micromechanical test and dynamic contact angle measurement. The IFSS of alkaline and silane-treated Jute fiber/PP composites increased, whereas after hydration, the IFSS of the untreated, alkaline- and silane-treated Jute fibers/PP composites decreased due to swelled fibrils by water infiltration. The interfacial adhesion of silane treated fiber/PP composites was higher than alkaline-treated or the untreated cases. The surface energies of Jute fiber treated under various conditions were obtained using dynamic contact angle measurement. Especially after hydration, the thermodynamic work of adhesion was calculated by considering water interlayer, which indicated the stability of IFSS between silane treated Jute fiber and PP matrix showing better than others.

• Journal of Adhesion and Interface
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• v.3 no.4
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• pp.37-43
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• 2002

A number of thin-film deposition technologies have been developed. However, even a thin film whose properties are excellent may not be used as long as the adhesion strength between the thin film and the substrate is poor. For thin films, the adhesion strength is as important as the properties. In the present article, relation between interface structure and thin film adhesion, and factors affecting thin film adhesion are reviewed. Two kinds of factors, internal factors and external factors, affect thin film adhesion. Such factors as composition, structure, and reactivity of both thin film and substrate as well as surface roughness of the substrate and residual stress of the thin film belong to internal factors. And such factors as load, temperature, humidity, and corrosive environment belong to external factors. It is also reviewed that how we can control the internal factors and the external factors to enhance or keep the adhesion strength.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.4
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• pp.413-420
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• 2012

An aluminum foil-laminated sheet is a laminated steel sheet on which aluminum foil is adhesively bonded. It is usually used on the outer panel of home appliances to provide an aluminum feeling and appearance on the surface of the product. The delamination of aluminum foil is one of the main problems during the stretch forming process. The purpose of this study is was to determine the delamination limit of an aluminum foil-laminated sheet in the stretch forming process. The delamination was dependent on the bonding strength between aluminum foil and steel sheet. The fracture behavior of the interface between the aluminum foil and the steel sheet was described by a cohesive zone model. A finite element was conducted with the cohesive zone model to analyze the relationship between the delamination limit and the bonding strength of the interface. The interface bonding strength was evaluated by lap shear and T-peel test. The delamination limit of the aluminum foil-laminated sheet was determined by using the bonding strength of the steel sheet. The delamination limit was also verified by the Erichsen test.

• Journal of Adhesion and Interface
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• v.14 no.4
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• pp.197-211
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• 2013

Surfactants which have ability to decrease surface tension through surface activation between the interfaces are used as essential major raw materials for detergents and cosmetics. Typical synthetic detergents such as EO (ethylene oxide), LAB (linear alkylbenzene) are made from chemical surfactant derived from petrochemicals, therefore, they are responsible for major environment contaminations and ecosystem destruction, especially of rivers and also cause atopic dermatitis through strong skin stimulus of these small molecular's powerful permeability and lead to cancers if they get into organs through capillary. Now worldwide interest is increasing to develop new natural surfactants and biosurfactants as ecological, biodegradabl, harmless and multi-functional new amphiphillic materials which replace these synthetic surfactants.

• Journal of Adhesion and Interface
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• v.13 no.4
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• pp.182-187
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• 2012

In making emulsion-type pressure sensitive adhesive (PSA), environmentally friendly sorbitan nonionic surfactants having various chemical structures were prepared and used to find out the possibility of substituting the traditional nonyl-phenyl nonionic surfactant (NPE40) by comparing their adhesive properties. Results exhibited that the PSA used NSR10-series and Tween 60 showed better adhesive properties in initial ball tack, peel strength and holding power than those of NPE40. The reason for this is their particular chemical structure and the proper ratio of hydrophobic groups to the ethylene oxide groups.

• Journal of Adhesion and Interface
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• v.19 no.4
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• pp.145-153
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• 2018

In this study, adhesion promoters with acrylate and carboxylic acid moiety were synthesized from malenized polybutadiene and 2-hydroxyethyl acrylate for producing adhesive film with low water absorption and high adhesion. The surface properties, adhesion strength, mechanical properties and water absorption of adhesive films were characterized according to the amount of acrylate and carboxylic acid in the synthesized adhesion promoters. As the carboxylic acid in the adhesion promoters increased, the adhesion strength showed a tendency to increase and the mechanical properties also improved compared to the commercial adhesion promoter. The compatibility of adhesion promoters improved remarkably due to the presence of polybutadiene (hydrophobic nature), maleic anhydride (hydrophilic nature) and carboxylic acid (hydrophilic nature).

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.2
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• pp.40-47
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• 2008

It is known that the adhesive interface testing of the rocket motor using the ultrasonic wave is superior to the other testing methods about the ability to economical detect the defects. But, the signal analysis of the ultrasonic wave takes a lot of time and efforts because the time interval of the transmitted pulse and the received pulse is too short to separate the reflected signals due to the multi-layers of the rocket motor. The ultrasonic testing of rocket motor have only applied to the automatic system about extremely limited areas like the debond in adhesive interface between the motor case and the insulator. In this study the new technique to detect the debond between the liner and the propellant using the property of the resonance and the lamb waves instead of the existing ultrasonic testing was described.