• The Journal of Korean Academy of Prosthodontics
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• v.32 no.2
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• pp.212-224
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• 1994

The purpose of this study was to evaluate and compare film thickness of five kinds of resin luting cements [Comspan, Panavia Ex, Maryland bridge adhesive, All-bond C & B cementation kit, and Super-bond C & B]. Zinc-phosphate cement and glass-ionomer cement were used as the control group. In order to measure the film thickness the methods used were in broad compliance with ADA Specification No. 8, a tapered-die system that simulates clinical conditions more closely, and the connected tapered-die system that simulates bridge conditions. The inorganic filler size of resin cements was also examined with scanning electron micrographs. The results were obtained as follows ; 1. The film thickness of resin cements was increased in the order of Comspan, Panavia Ex, Super-bond C & B, Maryland bridge adhesive, and All-bond C & B cementation kit. Maryland bridge adhesive and All-bond C & B cementation kit showed significantly higher film thickness than the control group(p<0.01). 2. For all resin cements, there was a significant difference of film thickness between the ADA method and the tapered-die system. Generally, the tapered-die system demonstrated lower film thickness than the ADA method(p<0.01). 3. There was no significant difference in film thickness between the tapered-die system and the tapered-die bridge system in all resin cements(p<0.01). 4. The scanning electron microscope showed that the cement with larger filler had a tendency to be higher in film thickness.

• Journal of the Korean Society of Safety
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• v.25 no.1
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• pp.1-8
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• 2010

The tensile and fatigue experiments were conducted with tensile-shear specimens for investigating the strength of adhesive bonded and mechanical press joints of SPCC steel sheet used in the field of the automobile industry. The optimal punch press force was evaluated 50kN for combining epoxy adhesive bonding and mechanical press joining with a diameter of 8.3mm using SPCC sheet with a thickness of 0.8mm. The combining epoxy adhesive bonding and mechanical press joining exhibits the maximum tensile force of 750N. The fatigue strengths of the combination of adhesive bond and mechanical press joint and pure adhesive joint were evaluated 370N and 320N at 106cycles, respectively. These values correspond to 22% and 20% of their maximum tensile forces, respectively. However, the fatigue strength of the combination of adhesive bond and mechanical press joining was much lower than that of pure mechanical press joining.

• Computers and Concrete
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• v.15 no.3
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• pp.337-355
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• 2015

In this scientific work, an improved analytical solution for adhesive stresses in a concrete beam bonded with the FRP plate is developed by including the effect of the adherend shear deformations. The analysis is based on the deformation compatibility approach where both the shear and normal stresses are assumed to be invariant across the adhesive layer thickness. The shear stress distribution is supposed to be parabolic across the depth of the adherends in computing the adhesive shear stress and Timoshenko's beam theory is employed in predicting adhesive normal stress to consider the shear deformation. Numerical results from the present analysis are presented both to demonstrate the advantages of the present solution over existing ones and to illustrate the main characteristics of adhesive stress distributions.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.3
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• pp.377-387
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• 2006

The objective of this study was to evaluate the influence of multiple adhesive coatings on the thickness of hybrid and adhesive layer and shear bond strength(SBS) of self-etch adhesives and self-etch primer adhesives. The buccal or lingual crown dentin of extracted human molars was used. Self-etch adhesives or self-etch primer adhesives were applied 1, 2 and 3 times on the dentin before light curing. In another group adhesives were reapplied after light curing first layer. Treated surfaces were prepared to measure the thickness of hybrid and adhesive layer with SEM, and shear bond strength to dentin using an Instron machine. The following results were obtained : 1. The adhesive layers increased with the number of coatings(p<0.05) with all adhesives. Adpor Prompt L-Pop and Xeno III were significantly thinner than self-etch primer adhesives (p<0.05). 2. The thickness of hybrid layers increased with the number of coatings (p<0.05). 3. The shear bonding strength of Unifil Bond and Clearfill SE Bond were higher than Scotchbond Multipurpose Plus and Adpor Prompt L-Pop (p<0.05), and similar with Xeno III. 4. The shear bond strength increased significantly with the number of coatings in Adpor Prompt L-Pop(p<0.05), but decreased at 3 times in AdheSE Bond(p>0.05). 5. In Adpor Prompt L-Pop and Xeno III, the shear bond strength decreased when adhesives were reapplied after curing the first adhesive layer.

• Restorative Dentistry and Endodontics
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• v.35 no.2
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• pp.69-79
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• 2010

The purpose of this study was to evaluate the effect of film thickness of various resin cements on bonding efficiency in indirect composite restoration by measurement of microtensile bond strength, polymerization shrinkage, flexural strength and modulus, fractographic FE-SEM analysis. Experimental groups were divided according to film thickness (< $50\;{\mu}m$-control, $50\;{\mu}m$-T50, $100\;{\mu}m$-T100, $150\;{\mu}m$-T150) using composite- based resin cements (Variolink II, Duo-Link) and adhesive-based resin cements (Panavia F, Rely X Unicem). The data was analyzed using ANOVA and Duncan's multiple comparison test (p < 0.05). The results were as follows ; 1. Variolink II showed higher microtensile bond strength than that of adhesive-based resin cements in all film thickness (p < 0.05) but Duo-Link did not show significant difference except control group (p > 0.05). 2. Microtensile bond strength of composite-based resin cements were decreased significantly according to increasing film thickness (p < 0.05) but adhesive-based resin cements did not show significant difference among film thickness (p > 0.05). 3. Panavia F showed significantly lower polymerization shrinkage than other resin cements (p < 0.05). 4. Composite-based resin cements showed significantly higher flexural strength and modulus than adhesive-based resin cements (p < 0.05). 5. FE-SEM examination showed uniform adhesive layer and well developed resin tags in composite-based resin cements but unclear adhesive layer and poorly developed resin tags in adhesive-based resin cements. In debonded surface examination, composite-based resin cements showed mixed failures but adhesive-based resin cements showed adhesive failures.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.9
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• pp.832-837
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• 2006

Antennas were fabricated by physical(adhesive) and chemical(deposition+plating) method on organic-inorganic composite material. And antennas were measured dielectric constant and gain. Dielectric constant of antennas were fabricated by physical method was decreased with increase of adhesive tape thickness and number of conduction material composition. But antennas were fabricated by chemical method was reached to 90 % of dielectric material. Gain of antennas were fabricated by physical method was decreased with increase of adhesive tape thickness. But they were unrelated with conduction material composition. The other side antennas were fabricated by chemical method excelled more 0.8 dBic than antennas were fabricated by physical method in gain of antenna. Finally, chemical method can expect excellent product process because it can produce smaller size, higher gain and elimination of many handworks.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.3
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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.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.699-700
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• 2010

• Journal of the Society of Disaster Information
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• v.15 no.2
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• pp.259-267
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• 2019

Purpose: In this paper adhesive-bonded cylindrical lap joints are analyzed by assuming that the adherends are elastic and the adhesive is linearly viscoelastic. Method: The distribution of the stresses in the adhensive is evaluated using the Finite Element Method. Nuverical examples for identical and different adherends bonded through a four parameter viscoelastic solid adhesive are illustrated. Results: The stress distribution in the adhesive layer with respect to time is shown. The stress distribution in the adhesive layer with respect to time is shown. The results are also shown that adherend thickness and elastic modulus give effect on the normalized stress. Conclusion: In this study, the stress distribution of the adhesive layer of the wrapped cylindrical body considering the viscoelasticity of the adhesive layer was numerically analyzed by using a four - element elastomer model.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.04a
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• pp.149-153
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• 2000

Substituting composite structures for conventional metallic structures has many advantages because of higher specific stiffness and specific strength of composite materials. In this work, one-piece propeller shafts composed of carbonfepoxy and glass/epoxy composites were designed and manufactured for a rear wheel drive automobile satisfying three design specifications, such as static torque transmission capability, torsional buckling and the fundamental natural bending frequency. Single lap adhesively bonded joint was employed to join the composite shaft and the aluminum yoke. For the optimal adhesive joining of the composite propeller shaft to the aluminum yoke, the torque transmission capability of the adhesively bonded composite shaft was calculated with respect to bonding length and yoke thickness by finite element method and compared with the experimental result. Then an optimal design method was proposed based on the failure model which incorporated the nonlinear mechanical behavior of aluminum yoke and epoxy adhesive. From the experiments and FEM analyses, it was found that the static torque transmission capability of composite propeller shaft was maximum at the critical yoke thickness, and it saturated beyond the critical length. Also, it was found that the one-piece composite propeller shaft had 40% weight saving effect compared with a two-piece steel propeller shaft.