• Restorative Dentistry and Endodontics
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• v.32 no.4
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• pp.377-384
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• 2007

Present tooth bonding system can be categorized into total etching bonding system (TE) and self-etching boding system (SE) based on their way of smear layer treatment. The purposes of this study were to compare the effectiveness between these two systems and to evaluate the effect of number of themocycling on microleakage of class V composite resin restorations. Total forty class V cavities were prepared on the single-rooted bovine teeth and were randomly divided into four experimental groups: two kinds of bonding system and another two kinds of thermocycling groups. Half of the cavities were filed with Z250 following the use of TE system, Single Bond and another twenty cavities were filled with Metafil and AQ Bond, SE system. All composite restoratives were cured using light curing unit (XL2500, 3M ESPE, St. Paul, MN, USA) for 40 seconds with a light intensity of $600mW/cm^2$. Teeth were stored in distilled water for one day at room temperature and were finished and polished with Sof-Lex system. Half of teeth were thermocycled 500 times and the other half were thermocycled 5,000 times between $5^{\circ}C$ and $55^{\circ}C$ for 30 second at each temperature. Teeth were isolated with two layers of nail varnish except the restoration surface and 1 mm surrounding margins. Electrical conductivity (${\mu}A$) was recorded in distilled water by electrochemical method. Microleakage scores were compared and analyzed using two-way ANOVA at 95% level. From this study, following results were obtained: There was no interaction between variables of bonding system and number of thermocycling (p = 0.485). Microleakage was not affected by the number of thermocycling either (p = 0.814). However, Composite restoration of Metafil and AQ Bond, SE bond system showed less microleakage than composite restoration of Z250 and Single Bond, TE bond system (p = 0.005).

• Restorative Dentistry and Endodontics
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• v.30 no.6
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• pp.450-460
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• 2005

The aim of this study was to evaluate the effect of cavity shape, bond quality of bonding agent and volume of resin composite on shrinkage stress developed at the cavity floor. This was done by measuring the shear bond strength with respect to iris materials (cavity shape , adhesive-coated dentin as a high C-factor and Teflon-coated metal as a low C-factor), bonding agents (bond quality: $Scotchbond^{TM}$ Multi-purpose and Xeno III) and iris hole diameters (volume; 1mm or 3mm in $diameter{\times}1.5mm$ in thickness). Ninety-six molars were randomly divided into 8 groups ($2{\times}2{\times}2$ experimental setup). In order to simulate a Class I cavity, shear bond strength was measured on the flat occlusal dentin surface with irises. The iris hole was filled with Z250 restorative resin composite in a bulk-filling manner. The data was analyzed using three-way ANOVA and the Tukey test. Fracture mode analysis was also done When the cavity had high C-factor, good bond quality and large volume, the bond strength decreased significantly The volume of resin composite restricted within the well-bonded cavity walls is also be suggested to be included in the concept of C-factor, as well as the cavity shape and bond quality. Since the bond quality and volume can exaggerate the effect of cavity shape on the shrinkage stress developed at the resin-dentin bond, resin composites must be filled in a method, which minimizes the volume that can increase the C-factor.

• Journal of Welding and Joining
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• v.13 no.2
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• pp.106-114
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• 1995

The characteristics of adhesive bonded joint of steels for automobile were investigated. Shear and tear strength were tested and analyzed for the joints of cold rolled steel sheets bonded with three kinds of epoxy and urethane based adhesive. The results showed that the tensile shear strength and the tear strength of adhesive joint were affected by the shape of adhesive joint such as the length and width of adhesive joint. The thickness of adhesive layer was very important factor affecting the bonding strength. The shear strength increased with decrease of the thickness of adhesive layer, while the tear strength decreased as the thickness of adhesive layer decreased. In comparison with the strength of spot welded joint, the shear strength of adhesive Joint was higher than that of spot welded joint, but the tear strength of adhesive Joint was lower than that of spot welded joint.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.23-23
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• 2003

PCB 회로기판용 전해동박은 드럼형태의 음극 표면에 연속적으로 전기 도금한 후 벗겨내어 권취하는 원박 제조공정과 접착성, 내열성, 내화학성, 방청성을 부여하기 위한 후처리 공정으로 나눈다. 이 후처리 공정 중 동박과 수지와의 접착성을 부여하기 위해 일반적으로 전기도금을 통해 조화(Nodule)처리를 실시하는데, 최근 LCD, PDP 등의 평판 디스플레이 장치의 구동칩이 실장되는 TCP용 동박의 경우 2$\mu\textrm{m}$이하의 낮은 조도(Rz)와 함께 높은 접착강도(Peel Strength)가 요구되고 있다. 그러나, Reel to Reel 형태의 연속도금공정으로 진행되는 조화처리에 있어 일반 비이커 실험결과는 실제 양산공정과의 재현성에 있어서 상당한 제한성이 노출된 바 있다. 이에 본 연구에서는 Reel to Reel 형태의 연속도금공정을 모사 할 수 있는 실험장치를 설계, 제작하여 동박표면의 노듈형성에 있어 주요인자를 정량적으로 분석하였다.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.123-127
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• 2003

액상실리콘으로 이루어진 초고압전력케이블용 프리몰드 접속재의 반도전-절연체 계면접합체를 다양한 제조조건과 조합별로 제조하여 계면접착력에 대한 영향을 검토하였다. 후가교적용 시 계면접착력이 강화되며 grade조합에 따른 특성차이가 존재하였다. 하지만 고온 장시간의 후가교 조건에서는 계면간의 화학적 결합력의 저하로 인해 오히려 접착력이 낮아지기도 하였다. 절연 RTV와의 계면접착성은 S-1재료가, 절연 LSR의 경우에는 S-3 재료가 가장 우수하였으며 도전안정성 측면에서도 S-3 재료가 상대적으로 유리하였다. 매입형 전극체를 제조하여 절연파괴거동을 연구한 결과 계면접착성과의 직접적인 상관관계는 크지 않음을 알 수 있었다.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.171-172
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• 2009

A Bonded Concrete Overlay is a layer of concrete bonded to the top of an existing pavement to rehabilitate it, to restore and increase its structural and functional capabilities and forming a monolithic structure with the existing pavement. This study focuses on the field application of BCO by very early strength latex modified concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.282-283
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• 2014

An active study on UHPC, which has been recently used in high-rise building and bridges, is in progress. However, research on adhesion strength of normal concrete and UHPC is required to be studied due to the lack of information. In this study, experimental research progress for adhesion strength (shear strength of adhesive surface) evaluation of Bi-compressive strength concretes (UHPC, Normal concrete) is proceeded. First, specimens using glue are produced and surface treatment methods of concrete bonded section are considered. Second, Direct Shear test is applied on concrete bonded section of UHPC (80~180MPa) and Normal Concrete (NC). As a result of this study, it is confirmed that bond strength is deteriorated as the difference of intensity ration of NC and UHPC increases.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.325-326
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• 2010

In this study, we prepared three kinds of substrate for the adhesion strength test of cementitious tile adhesive. As a result, the maximum adhesion strength is obtained from the concrete substrate specified in ISO 13007 regardless of curing condition of tile cement specimens.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.8 s.179
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• pp.2022-2031
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• 2000

Since the surface roughness of adherends affects much the strength of adhesivelybonded joints, the effect of surface roughness on the fatigue life of adhesively bonded tubular single lap joints was investigated analytically and experimentally by fatigue torsion test. The stiffness of the interfacial layer between adherends and adhesive was modeled as a normal statistical distribution function of surface roughness of adherends. From the investigation, it was found that the optimum surface roughness of adherends for the fatigue strength of tubular single lap joints was dependent on bondthickness and applied load.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.93-94
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• 2012

Recently outside insulation is applied on the building. Adhesion mortar and anchor are used fixing method of outside insulation. However, a research on proper Adhesion Strength is not performed. So outside insulation exfoliate from building in rainy with winds. Therefore, this research suggest proper adhesion strength about conjugation method of outside insulation. As a result, adhesion way using the adhesive mortar + anchor is best. And proper adhesion strength is over 1,065 N.