• 한국생산제조학회지
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• 제7권1호
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• pp.58-68
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• 1998

Advantages of adhesively bonded joints and techniques of weight reduction have led to increasing use of structural adhesives such as LSI(large scale integration) package, automobile, aircraft in the various industries. In spite of such wide applications of adhesively bonded joints, the evaluation method of bonding strength has not been established. Stress singularity occurs at the interface edges of adhesively bonded joints and it is required to analyze it. In this paper, the stress singularity using 2-dimensional elastic boundary element method (BEM) with the changes of the lap length and adhesive for single lap joint was analyzed, and experiments of strength evaluation were carried out. As the results, the evaluating method of bonding strength considering stress singularity at interface edges of adhesively bonded joints and stress intensity factor of interface crack have been proposed in static and fatigue test.

• Journal of Welding and Joining
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• 제22권2호
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• pp.38-45
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• 2004

Ultrasonic signals transmitted through adhesively bonded plates were used to evaluate parameters related to attenuation and frequency in the adhesively bonded joint. The kinds of bonding materials with a different bonding thickness of constant pressure were used. And ultrasonic diagnosis was evaluated by p-wave sensor of 10MHz. FFT has been performed to determine bond-layer parameters such as effective thickness and frequency for adhesively bonded joint of A16061 plates in comparison with measured to theoretical ratios. When variable thickness exists, the ultrasonic spectrum was changed the frequency wave. The more materials thickness and the higher the frequency, the larger shift was observed. Measured ratios for cases of bond thickness and variety bonding materials are then used to determine bond parameters. The results show that the technique can be applied to the characterization of adhesively bonded joint.

• Journal of Welding and Joining
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• 제30권6호
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• pp.62-67
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• 2012

In this study, the bonding strengths of adhesively bonded joints are experimentally investigated. A series of lap-shear tests are conducted using single lap type adhesive joints. In order to analyse the joint fabrication factors that affected the bonding strength, the parametric tests are conducted with various thickness of adhesive, surface roughness and fillet of adhesive. In addition, for the comparative study with the welded joint, lap-shear tests using specimens with 2 welded sides and 4 welded sides are also carried out. The quantitative results of the strength analysis are summarized, and some proposals are made on setting up testing standards for adhesively bonded joints.

• 한국생산제조학회지
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• 제21권3호
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• pp.439-445
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• 2012

The stress singularity for the excess adhesive on interface of adhesively bonded joint was investigated by using the 2-dimensional elastic boundary element method (BEM). To establish a reasonable strength evaluation method and a fracture criterion for the excess adhesive of interface in adhesively bonded joint, it is necessary to evaluate fracture parameters with various bonding conditions. Under the variations of adhesively bonded thickness (h) and diameter (d) for the excess adhesive, a stress analysis was performed, and from the results, the stress singularity index (${\lambda}$) and the stress singularity factor (${\Gamma}$) were calculated. The variations have a great influences on the stress singularity for the excess adhesive of interface in adhesively bonded joint, and the ${\Gamma}$ is reduced as the "h" and "d" increase.

• 한국안전학회지
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• 제24권3호
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• pp.7-12
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• 2009

The tensile and fatigue experiments were conducted with tensile-peel specimens for investigating on strength of adhesively bonded and mechanical press joints of aluminum sheet used in the field of the automobile industry. The combining epoxy adhesive bonding and mechanical press joining exhibits an increase in joining force as a result of interaction between static forces of the two joining methods. The fatigue strength of pure adhesive joint was measured as 91% of that of the combination of adhesive bond and mechanical press joint, suggesting that the interaction between the bonding and mechanical joining was about 9%.

• 마이크로전자및패키징학회지
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• 제31권2호
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• pp.1-8
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• 2024

Bonding wires are composed of conductive metals of Au, Ag & Cu with excellent electrical conductivities for transmitting power and signals to wafer chips. Wire metals do not provide electrical insulation, adhesion promoter and corrosion passivation. Adhesion between metal wires is extremely weak, which is responsible for wire cut failures during thermal cycling. Organic coating for electrical insulation does not satisfy bondability and manufacturability, and it is complex to apply very thin organic coating on metal wires. Automotive packages require enhanced reliability of packages under harsh conditions. LED and power packages are susceptible to wire cut failures. Contrary to conventional OCB behaviors, forming gas was not required for free air ball formation for both Ag and Pd-coated Cu wires with Al₂O₃ passivation.

• 한국정밀공학회지
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• 제17권6호
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• pp.103-110
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• 2000

In this study, the angular twist type torque-meter was designed and manufactured with STS 304 and fiber-reinforced composite materials to improve the dynamic properties of the existing torque-meter. From the Experimental and analytical results, it was found that the dynamic characteristics of co-cured bonded torque-meter rotating shaft were better than those of the adhesively and unreinforced torque-meter rotating shaft. For the torque-meter rotating shaft manufactured by co-cured bonded with the glass fiber-epoxy composite and with a stacking sequence of $[$\pm$30$^{\circ}$/STS304]_{2s}$, the natural frequency and the radial spring constant were increased by 64% and 137% compared to those of the unreinforced torque-meter rotating shaft.

• 대한기계학회논문집A
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• 제26권12호
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• pp.2662-2669
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• 2002

Recently structural applications of adhesive bonding method have been increased extensively in automobile industry. Adhesively-bonded joints which are used in automobile field are exposed to various environmental conditions. In this study, several environmental factors were concerned to evaluate their effects on the adhesive strength such as air temperature, water temperature, exposed time in water. The specimens are exposed for 1, 10 and 100 hours at various air temperatures to evaluate the effects of the air and water temperature on the adhesive strength. It is proved that the adhesive strength decrease with rising the air and water temperature, and the adhesive strength decrease steeply at the higher temperature with increasing the exposure time in water.

• 대한기계학회논문집
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• 제18권6호
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• pp.1412-1420
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• 1994

The adhesively bonded tubular double lap joint has better torque transmission capability and reliability in bonding operation than the single lap joint. In this paper, an analytic solution for the torque transmission capabilities and stress distributions of the adhesively bonded tubular double lap joint was derived assuming the linear properties of the adhesive and adherends. From the calculation, it was found that the torque transmission capabilities of the double lap joint was more than 40% larger compared to that of the single lap joint.

• 대한치과의사협회지
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• 제49권5호
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• pp.265-278
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• 2011

The introduction of zirconia-based materials to the dental field broadened the design and application limits of, all-ceramic restorations. Most ceramic restorations are adhesively luted to the prepared tooth, however, resin bonding to zirconia components is less reliable than those to other dental ceramic systems. It is important for high retention, prevention of microleakage, and increased fracture resistance, that bonding techniques be improved for zirconia systems. Strong resin bonding relies on micromechanical interlocking and adhesive chemical bonding to the ceramic surface, requiring surface roughening for mechanical bonding and surface activation for chemical adhesion. In many cases, high strength ceramic restorations do not require adhesive bonding to tooth structure and can be placed using conventional cements which rely only on micromechanical retention. However, resin bonding is desirable in some clinical situations. In addition, it is likely that strong chemical adhesion would lead to enhanced long-term fracture and fatigue resistance in the oral environment.