• Journal of Welding and Joining
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• v.18 no.4
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• pp.96-103
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• 2000

This study investigated the effects of bonding temperature and bonding atmosphere on high temperature mechanical properties of transient liquid phase(TLP) bonded joints of heat resistant alloy using MBF-50 insert metal. Specimens were bonded at 1,423~1,468K for 600s. Microconstituents of {TEX}$Cr_{7}(C,B)_{3}${/TEX}were formed in the bonded region when the bonding temperature was low. The amount of microcostituents in the bonded layer decreased with increasing the bonding temperature, and the microconstituents in the bonded layer disappeared at the bonding temperature above 1,468K. The tensile strength of the joints at elevated temperatures increased with the increase the bonding temperature and was the same level as one of the base metal in the bonding temperature over 1,453K. Microstructure and alloying element distributions of the bonded region bonded in Ar and $N_2$atmosphere were similar to those of the bonded in vacuum. The creep rupture strength and rupture lives of joints were almost identical to those of base metal.

• Korean Journal of Materials Research
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• v.5 no.2
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• pp.191-196
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• 1995

Self-bonding strength developed at the interface of amorphous PEEK films is highly sensitive to the processing variables(time, temperature, and pressure) during the bonding process. In order to examine the effects of these processing variables, amorphous PEEK films were bonded at various bonding conditions and the resultant interfacial bond strengths were measured using a modified single lap-shear test. Experimental results showed that the developed self-bonding strength increases with increase in bonding temperature and is directly proportional to the bonding time raised to the 1/4 power. The applied pressure seems only to produce better wetting at the beginning stage of the bonding process. Conclusively, the self-bonding of amorphous PEEK films provides a great potential for developing excellent bond strength approaching the strength of the parent material without any adhesives in structural applications.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.293-298
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• 1995

This study experimentally evaluate the bonding performance of repair and strengthening materials. It is very important problem to justify bonding properties between repair and strengthening materials and old concrete. Many previous research and investigation showed that bonding strength of reinforcing materials determines the strengthening effect and the durability of repair work. Therefore, menifestation of bonding properties and the improvement of bonding performance of repair and strengthening materials are very important. In order to improve the perforamnce of repair work, it needs to investigate the behavior of bonding materials, such as stress distribution along the bonding area and the long term performance of the material. The target repair methods are steel plate addition technique and repair mortar method, and the test parameters studied in this paper include epoxy thickness, bonding surface texture, and bonding area.

• Journal of Welding and Joining
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• v.20 no.5
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• pp.93-98
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• 2002

The effect of bonding misfit on single crystallization of transient liquid phase (TLP) bonded joints of single crystal superalloy CMSX-2 was investigated using MBF-80 insert metal. The bonding misfit was defined by (100) twist angle (rotating angle) at bonded interface. TLP bonding of specimens was carried out at 1523K for 1.8ks in vacuum. The post-bond heat treatment consisted of the solution and sequential two step aging treatment was conducted in the Ar atmosphere. The crystallographic orientation analysis across the TLP bonded joints was conducted three dimensionally using the electron back scattering pattern (EBSP) method. EBSP analyses f3r the bonded and post bonded heat treated specimens were conducted. All bonded joints had misorientation centering around the bonded interface for as-bonded and post-bond heat treated specimens with rotating angle. The average misorientation angle between both solid phases in bonded interlayer was almost identical to the rotating angle at bonded interface. HRTEM observation revealed that the atom arrangement of both solid phases in bonded interlayer was quite different across the bonded interface. It followed that grain boundary was formed in bonded interface. It was confirmed that epitaxial growth of the solid phase occurred from the base metal substrates during TLP bonding and single crystallization could not be achieved in joints with rotating angle.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.9
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• pp.98-105
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• 1995

Recent microwave IC's reach to the extent of high operating frequencies at which bonding wires limit their performance as dominant parasitic components. Double bonding wires separated by an internal angle have been firstly characterized using the Method of Moments with the incorporation of the ohmic resistance calculated by the phenomenological loss equivalence method. For a 30$^{\circ}$ internal angle, the calculated total reactance is 45% less than that of a single bonding wire due to the negative mutual coupling effect. The radiation effect has been observed decreasing the mutual inductance, whereas for parallel bonding wires it greatly increases the mutual inductance. This calculation results can be widely used for designing and packaging of high frequency and high density MMIC's and OEIC's.

• Proceedings of the KWS Conference
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• 2010.05a
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• pp.28-28
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• 2010

The secondary barrier of cargo containment for membrane LNG tank is composed of composite materials such as rigid triplex (rigid secondary barrier, RSB) and flexible triplex (flexible secondary barrier, FSB). RSB and FSB are adhered to each other using an epoxy adherent and the quality of the secondary barrier depends on the bonding strength between them. The bonding strength between RSB and FSB is greatly influenced by the surface condition of RSB prior to joining. In this study, the effect of surface condition prior to joining on the joint strength and the fracture mode occurred between RSB and FSB have been examined in order to establish a proper surface treatment method for improving the bonding strength at the temperature of $-170^{\circ}C$.

• Journal of Families and Better Life
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• v.17 no.2
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• pp.121-136
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• 1999

The purpose of this study was to investigate the effect of parent-bonding patterns & environmental variables on rural adolescent's trait-anxiety. The main results were as follows. Frist mother had more affection and father had more overprotection in parent-bonding patterns. Trait-anxiety was the level of medium. Second home atmosphere home life satisfaction parents' scolding health conditions allowance satisfaction friendship the relationship with home teachers school life satisfaction and teacher's scolding were significnat variables on trait anxiety Third an analysis of parent-bonding relationship environmental variable and trait-anxiety showed that school life satisfaction family atmosphere friendship and health conditions were the most crucial environmental variable while father's care and mother's overprotection were the most crucial parent-bonding variables on rural adolescent's trait-anxiety.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.10
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• pp.857-863
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• 2014

In this work, we introduce various bonding technologies for 3D package and suggest Insert-Bump bonding (ISB) process newly to stack multi-layer chips successively. Microstructure of Insert-Bump bonding (ISB) specimens is investigated with respect to bonding parameters. Through experiments, we study on find optimal bonding conditions such as bonding temperature and bonding pressure and also evaluate in the case of fluxing and no-fluxing condition. Although no-fluxing bonding process is applied to ISB bonding process, good bonding interface at $270^{\circ}C$ is formed due to the effect of oxide layer breakage.

• Restorative Dentistry and Endodontics
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• v.20 no.1
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• pp.1-16
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• 1995

The purpose of this study was to investigate the effect of dentin bonding agents on the bond strength of composite resin restorations in case of applying the dentin bonding agents to acid etched enamel surfaces. Freshly extracted 364 bovine anterior teeth were selected as a adherents. 320 enamel specimens were divided into two groups(unetched group (1) and etched group (2) for testing the shear bond strength, 40 specimens were used for the hardness testing, and 4 specimens of rest were to observe the resin-tag formation into etched enamel surfaces. All surfaces of enamel specimens were polished with 320~1500 SiC paper under continuous running water. In Group (1), 100 enamel specimens were polished and unetched. 220 polished enamel specimens in Group (2) were etched with 37 % phosphoric acid solution for 60 seconds, washed with water for 20 seconds, and dried with a light air pressure for 60 seconds. Three kinds of dentin bonding agents(Gluma, Prisma, Scotchbond 2) were evaluated the effect on the bond strength to conditioned enamel surfaces. Shear bond strengths were measured on the three cases such as a coating of primer only, a coating of sealer only, and a sequential coating of primer and sealer to acid etched enamel surfaces were compared with the bond strengths measured by the coating of enamel bonding agent followed by the bonding of composite resin (Photo clearfil bright, Kuraray, Japan) to unetched and acid etched enamel surfaces. In addition, the hardness tested on the adhesive fractured surface between composite resin enamel as a mean of evaluation of a factor whether the mechanical bond strengths were affected and the penetration of dentin bonding agents into etched enamel surfaces was also observed. Bond strengths were measured using the method of shear bond strength by a universal testing machine (Instron-4467, USA), statistical test were applied to the results using a one way analysis variance(ANOVA), and hardness was measured by the Vicker's Hardness Tester(MHT-i, Matsuzawa, Japan) and the penetration of the resins were observed by the SEM (Hitachi, S-2300, Japan). The following conclusions were drawn; 1. Enamel bonding agent showed to affect the improvement of bond strength of composite resin to enamel surface both unetched and etched. 2. Dentin bonding agents could be resulted in increase of bond strength to unetched enamel surface, but there were no statistical significances. 3. Bond strengths to etched enamel surface were significantly decreased with a coating of dentin primer only. 4. Coating of sealer only and coating of primer and sealer noticed the similar bond strengths of composite resin to etched enamel using the enamel bonding agents. 5. The applying method proved to be more effective than the kinds of dentin bonding agents on the bond strength of composite resin to etched enamel than the kind of dentin. 6. Vicker's hardness numbers of dentin bonding agents were lower than that of composite resin, but the degree of penetration of dentin bonding agents into etched enamel surfaces was excellent.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.4-4
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• 2009

Surface analysis on defective wire-bonding pads are performed in flash memory assembly. Week wire bonding may cause a significant effect on the final product reliability, and the surface condition of the aluminum bond pads is critical in terms of product reliability. To find out possible week bonding on semiconductor interconnects, ball sheer test (BST) has been performed. On some defective or week bonded pads, we have investigated the surface contents, assuming that the week bonding is induced from the surface conditions. AES and XPS are employed for the quantitative surface analysis on defective dies.