• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.534-540
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• 2001

One approach to testing the suitability of an adhesive joint for a particular application is to build and test to destruct ion a representative sample of the joint. The nondestructive test will not measure strength directly but will measure a parameter which can be correlated to strength. It is therefore, essential that a suitable nondestructive test is chosen and that its results are correctly interpreted. In this paper, typical defects found in adhesive joints are described together with their significance. The limits and likely success of current physical nondestructive tests are described, and future trends outlined.

• KCI Concrete Journal
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• 제12권1호
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• pp.91-99
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• 2000

A new type of retrof=t anchor bolt that uses deformed reinforcing bars and a commercial adhesive was developed and then an experimental study was carried out to determine the behavior of the anchors in direct shear. The steel-to-concl몫ete interface was tested. Plain concrete slabs with about 20-MPa compressive strength were used for 23 direct shear tests performed Test variables were anchor diameters (D16, D22. and D29) and edge effect. Three different shear tests were completed: simple shear, edge shear where anchors were pulled against the concrete core, and edge shear where anchors were pushed against the concrete cover In the simple and the edge shear tests where the anchors were pulled against the core, the theoretical dowel strength determined by (equation omitted) was achieved but with relatively large displacements. The shear resistances increased with the increasing displacements. In the edge shear test where the anchors were pushrd against the cover, the peak shear strengths signif=cantly lower than the theoretical dowel strength were determined due to cracks developed in concrete when the edge distance was 80 mm. The peak strengths were about 50% of the dowel strength for Dl6 bar. and about 25% or less of the dowel strength for D22 and D29 bars. Test results revealed that the edge shear where the anchor was pushed against the cover controled.

• 품질경영학회지
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• 제44권3호
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• pp.509-526
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• 2016

Purpose: We would like to find the alternative method for the weathering test on rubber coated fabrics and adhesive-coated fabrics for the military products, KS M 0706 (Sunshine carbon arc) to KS M ISO 4892-2 (Xenon arc). Methods: We measured the tensile strength of adhesive-coated fabrics and adhesive products treated with sunshine carbon arc and xenon arc during 100, 150 and 200 hours, respectively. All of the results were treated with statistical test, ANOVA method. We also validate the surface modifications caused by treatment method and time by using FT-IR ATR and, SEM. Results: In case of the thick adhesive-coated fabrics (app. 1 mm), there was no distinctive difference on tensile strength by treatment method and time. In case of the thin mask hood (app. 0.22 mm) and TENT (app. 0.5 mm), there was distinctive difference on tensile strength. Especially, carbon arc showed a huge lowering properties. We could validate the curing from light and moisture, and the functional group change from cross-linking and oxidation using FT-IR ATR. In case of IBS, there was a surface cracks on SEM images. In case of mask hood, there was no distinctive differences, except for a particle falling from decreased affinity between rubber and particles caused by carbon arc. Conclusion: We concluded that there was no problems for changing xenon arc weathering test with same treatment time on IBS, KM7, K21 and adhesive products. In case of TENT and mask hood, there was a difference in tensile strength in accordance with the change of the treated time and method.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 추계학술발표대회 개요집
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• pp.94-96
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• 2005

This paper is concerned with a fracture strength study of composite adhesive lap joints. The tensile and peel tests were carried out on specimen manufactured hybrid stacked composites such as the polyester and bamboo natural fiber layer. The main objective of the work was to test the failure strength of adhesive bonded joints using hybrid stacked composites with a polyester and bamboo natural fiber layer adjacent to the fiber orientation. From results, the load directional orientation, small amount and low thickness of bamboo natural fiber layer have a good effect on the tensile and peel strength of natural fiber reinforced composites. and these characters are have a great influence on fracture strength and failure shape of adhesive bonded joints using hybrid stacked composites in the difference of fiber orientation.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 춘계학술발표대회 개요집
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• pp.262-264
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• 2005

This paper is concerned with a fracture strength study of composite adhesive lap joints. The tests were carried out on specimen joints manufactured hybrid stacked joints such as the polyester and bamboo natural fiber layer. The main objective of the work was to test the fracture strength using hybrid fiber composites with a polyester and bamboo natural fiber layer adjacent to the spew fillet of adhesive bonded joints and hybrid stacked joints. The results are presented using tensile-shear strength graph and finite element analysis. The failure mechanisms are discussed in order to explain that spew fillet at the end of the overlap reduces greatly the adhesive shear and effects the tensile-shear strength in hybrid stacked joints.

• Elastomers and Composites
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• 제34권3호
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• pp.253-261
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• 1999

조성이 다른 접착제를 포함한 고무혼합물의 가교특성은 접착제 조성에서 탄닌이 많이 포함될수록 스코치 시간은 증가하였으며 경화속도는 다소 감소하는 것으로 보아 탄닌 분자의 크기와 형태 때문에 초기 가교반응을 지연시킴과 동시에 경화속도 역시 다소 지연됨을 알 수 있었다. 이들 고무혼합물의 인장물성 역시 탄닌이 많이 함유된 접착제를 고무에 혼합할수록 고무혼합물의 인장강도는 다소 감소하였다. 이는 탄닌이 많이 함유될수록 가교반응을 지연시켜 전체 고무혼합물의 가교도가 감소하기 때문일 것으로 사료되었다. 또한 접착제의 조성이 고무-섬유 접착에 미치는 영향을 보강코드로서 나일론 610 모노필라멘트를 사용하여 TCAT(Tire Cord Adhesion Test) 방법으로 조사하였다. 레소시놀-탄닌-포름알데히드-라텍스(RTFL) 접착제 조성에서 레소시놀 1 mole당 포름알데히드의 mole 비가 증가할수록 접착력은 증가하였고 대략 포름알데히드 5mole 이상에서 최적의 접착력을 나타냈다. 보강코드상의 접착제 수확량(DPU) 역시 최종 접착력에 영향을 미치지만, 나일론 610 모노필라멘트의 경우는 접착제 조성에 따른 DPU가 거의 일정하여 접착력의 차이는 접착제의 조성 중 탄닌의 거동 때문으로 해석될 수 있었다.

• Restorative Dentistry and Endodontics
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• 제40권1호
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• pp.23-29
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• 2015

Objectives: The aim of this study was to evaluate the effect of pre-etching on the bond strength of silorane-based composite specific adhesive system to dentin. Materials and Methods: Thirty human molars were randomly divided into 5 groups according to the different bonding strategies. For teeth restored with silorane-based composite (Filtek Silorane, 3M ESPE), the specific self-etching adhesive system (Adhesive System P90, 3M ESPE) was used with and without pre-etching (Pre-etching/Silorane and Silorane groups). Teeth restored with methacrylate based-composite (Filtek Z250, 3M ESPE) were hybridized with the two-step self-etching system (Clearfil SE Bond, Kuraray), with and without pre-etching (Pre-etching/Methacrylate and Methacrylate groups), or three-step adhesive system (Adper Scotchbond Multi-Purpose, 3M ESPE) (Three-step/Methacrylate group) (n = 6). The restored teeth were sectioned into stick-shaped test specimens ($1.0{\times}1.0mm$), and coupled to a universal test machine (0.5 mm/min) to perform microtensile testing. Results: Pre-etching/Methacrylate group presented the highest bond strength values, with significant difference from Silorane and Three-step/Methacrylate groups (p < 0.05). However, it was not significantly different from Pre-etching/Silorane and Methacrylate groups. Conclusions: Pre-etching increased bond strength of silorane-based composite specific adhesive system to dentin.

• 대한치과보철학회지
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• 제54권3호
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• pp.218-225
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• 2016

목적: 본 연구에서는 자가-접착 레진 시멘트의 접착 강도에 포스트의 표면 처리와 접착 시스템이 미치는 영향을 조사하고자 하였다. 재료 및 방법: 비슷한 치근 길이를 가진 48개의 사람 상악 단근치를 사용하여 160개의 시편을 제작하고 접착 시스템에 따라 4개의 군으로 분류하였다(no adhesive, Adper Single Bond 2, Clearfil SE Bond, Clearfil S3). 각 군은 포스트 표면 처리 방식에 따라 다시 4개의 군으로 세분하였다(no treatment, sandblast, silane, sandblast and silane). 포스트를(Parapost Fiber White) Rely X Unicem을 사용하여 접착하였다. 치아를 장축에 수직으로 1 mm 두께로 절단 하였다. Push-out test를 0.5 mm/분의 crosshead speed로 시행하였다. 2-way ANOVA, 1-way ANOVA 검정을 시행하였고 Tukey test를 통한 사후 검정을 시행하였다(${\alpha}=0.05$). 결과: Tukey test를 통한 사후 검정에서 접착 시스템에 따른 차이가 나타났다. Clearfil SE Bond가 가장 높은 접착 강도를 나타내었다. 결론: 상아질에 Clearfil SE bond를 사용하고 포스트를 실란 처리시 가장 높은 접착 강도를 나타내었다.

• 한국정밀공학회지
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• 제33권3호
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• pp.231-234
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• 2016

Pouch film is manufactured by laminating aluminum foil, polyamide film and polypropylene film with an adhesive or extrusion resin. However, a surface treatment is required for the aluminum because bonding does not occur easily between the aluminum foil and the polymer film. Thus, for this study, surface treatment experiments were performed in order to confirm the effect on adhesion strength. First, a variety of surface treatment solutions were coated on aluminum foil, and contact angle and surface morphology analysis was carried out for the surface-treated aluminum. For lamination of the surface-treated aluminum foil with polyamide film, a polyurethane base adhesive was prepared for the adhesive strength test specimens. The adhesive strength between the aluminum foil and the polyamide film of the resulting specimens was measured (UTM). With such an experiment, it was possible to evaluate the effect on adhesive strength of the various surface treatments.

• International Journal of Aeronautical and Space Sciences
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• 제18권1호
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• pp.56-62
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• 2017

Because adhesively bonded joints are used in many structural systems, it is important to predict accurate adhesive strengths. Composite aircraft with many joints are easily exposed to low temperatures and high relative humidity. This paper presents a humidity aging effect on the adhesive strength of a composite single-lap joint (SLJ). The adhesive strength of the SLJ is predicted using a finite element analysis with a cohesive zone model (CZM) technique. The humidity aging effect is evaluated based on the adhesive strength and CZM parameters. A lap joint test is carried out on the composite SLJ specimens, which are exposed for four months of 100% R.H. at $25^{\circ}C$. The predicted strengths are in good agreement with experimental data, and the actual crack propagation is satisfactorily simulated using the local CZM technique.