• Journal of Welding and Joining
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• v.31 no.6
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• pp.65-70
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• 2013

In joining Alumina to copper plate by Mo-Mn metallizing process, the effects of the composition of metallizing paste on the bonding strength were investigated. The bonding strength increased with increasing Mn amount in the paste up to 20% but followed by the decrease with addition of Mn. The maximum bonding strength reached 50MPa at 20%Mn when heated to $1550^{\circ}C$ for 60minute. The addition of Si to the metallizing powder increased the bonding strength of the joint by enhancing the mechanical bonding between the Alumina and the metallizing layer due to the decrease of layer viscosity with the addition of $SiO_2$. It is thought that MnO reacted with $Al_2O_3$ to yield $MnAl_2O_4$ spinel, forming a joint.

• 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.

• Journal of the Korea Concrete Institute
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• v.21 no.3
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• pp.275-282
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• 2009

The effects of surface treatment method of reinforcing fiber on the bonding strength between carbon fiber reinforced polymer rebar (CFRP rebar) and high strength concrete have been evaluated in this study. The structural PVA fiber is coated with a proprietary hydrophobicoiling agent and crimped type polyolefin based structural synthetic fiber is deformed with a geometrical modification were used for the reinforcing fiber. The compressive tests have been performed to evaluate the strength property of high strength concrete depending on the surface treatment method of fiber. The bonding property between the high strength concrete and the CFRP rebar was evaluated by means of direct bonding test. The test results indicated that the surface treatment method of fiber effect on the bonding behavior of high strength concrete and CFRP rebar. Also, as the development and propagation of splitting cracks were controled by adding fibers into the high strength concrete, the bonding behavior, bond strength and relative bonding strength of CFRP rebar and high strength concrete were significantly improved.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.107-113
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• 1982

The purpose of this study was to observe the tensile strength of composite resins to etched dentin surface with the various methods of placing bonding agent before composite resin or placing composite resin alone. Recently extracted 60 maxillary incisors were chosen. These were divided into 6 groups: Group I : Immediate Silar adaptation to the etched dentin surface with 37% phosphoric acid for 60 seconds without bonding agent. Group II : Immediate Silar adaptation to the etched dentin surface with 37% phosphoric acid for 60 seconds with bonding agent. Group III : Silar adaptation to the etched dentin surface with 37% phosphoric acid for 60 seconds after 5 minutes of bonding agent. Group IV : Immediate Enamelite adaptation to the etched dentin surfaces with 50% phosphoric acid for 120 seconds without bonding agent. Group V : Immediate Enamelite adaptation to the etched dentin surface with 50% phosphoric acid for 120 second s with bonding again. Group VI : Enamelite adaptation to the etched dentin surface with 50% phosphoric acid for 120 seconds after 5 minutes of bonding agent. All specimens were immersed in water at $37^{\circ}C$ for 24 hours before testing. The results were as follows: 1. The tensile strength of powder/liquid composite resin system was higher than that of pastel paste composite resin system. 2. The tensile strength of the composite resin group II, III, V, & VI with bonding agent was higher than that of the composite resin group I & IV without bonding agent. 3. The tensile strength of the composite resin group III & VI after 5 minutes added to bonding agent was higher than that of the composite resin group II & V immediately added to bonding agent.

• Korean Journal of Materials Research
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• v.12 no.10
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• pp.820-824
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• 2002

It is of importance to know that the bonding strength and interfacial stress of SOI wafer pairs to meet with mechanical and thermal stresses during process. We fabricated Si/2000$\AA$-SiO$_2$ ∥ 2000$\AA$-SiO$_2$/Si SOI wafer pairs with electric furnace annealing, rapid thermal annealing (RTA), and fast linear annealing (FLA), respectively, by varying the annealing temperatures at a given annealing process. Bonding strength and interfacial stress were measured by a razor blade crack opening method and a laser curvature characterization method, respectively. All the annealing process induced the tensile thermal stresses. Electrical furnace annealing achieved the maximum bonding strength at $1000^{\circ}C$-2 hr anneal, while it produced constant thermal tensile stress by $1000^{\circ}C$. RTA showed very small bonding strength due to premating failure during annealing. FLA showed enough bonding strength at $500^{\circ}C$, however large thermal tensile stress were induced. We confirmed that premated wafer pairs should have appropriate compressive interfacial stress to compensate the thermal tensile stress during a given annealing process.

• Journal of Technologic Dentistry
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• v.35 no.2
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• pp.105-112
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• 2013

Purpose: This study was to analyze the castability, surface oxide characteristic of Co-Cr alloy for porcelain fused to metal crown and the bonding strength of porcelain fused to metal crown. Co-Cr and Ni-Cr alloy for porcelain fused to metal crown was used for tests of the castability and surface oxide state and shear bonding strength by various porcelain. The aim of this study was to suggest the differences of result according to Co-Cr and Ni-Cr alloy. Methods: The kinds of alloy as test specimen was Co-Cr and Ni-Cr alloy. The castability index on the alloy specimens. The surfaces of two alloys were analyzed by SEM and EDX in order to observe oxide characteristic. And the shear test was performed by MTS. Results: The castability index of Co-Cr alloy was 96.8% and Ni-Cr alloy was 94.4%. The strongest bonding strength of Co-Cr alloy was shown 67.37 MPa. Conclusion: The shear bonding strength between Co-Cr alloy and EX3 porcelain was the strongest comparing with others. And all of each alloy was indicated as same level about the castability.

• Journal of Technologic Dentistry
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• v.35 no.4
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• pp.353-358
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• 2013

Purpose: This study was observation shear bonding strength by compositional change and firing step of a Ni-Cr alloy for porcelain fused metal crown. The aim of study was to suggest the material for firing step of Ni71-Cr14 alloy to development of alloy for porcelain fused to metal crown. Methods: The test was on the two kinds of Ni-Cr alloy specimens. The surfaces of two alloys were analyzed by EDX in order to observe oxide characteristic. And the shear test was performed by MTS. Results: The surface property and oxide characteristic analysis of oxide layer, weight percentage of Element O within $Ni_{71}Cr_{14}$ alloy measured 23.32wt%, and $Ni_{59}Cr_{24}$ alloy was measured 23.03wt%. And the maximum shear bonding strength was measured 58.02MPa between $Ni_{59}Cr_{24}$ alloy and vintage halo(H4 group). Conclusion: The surface property and oxide characteristic three kind of Ni-Cr alloy was similar. and shear bonding strength showed the highest bonding strength in H4 specimens.

• Current Photovoltaic Research
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• v.3 no.1
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• pp.1-4
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• 2015

In this study, we analyzed the correlation between mechanical and electrical properties of low-temperature conductive film (LT-CF) bonded silicon solar cells by a quadrant analysis (horizontal axis (peeling strength), vertical axis (power loss)). We found that a series of points with various bonding parameters such as bonding temperature, pressure and time were distributed in the different three regimes; weak regime (Q2: weak bonding strength and high power loss), moderate regime (Q4 : strong bonding strength and low power loss) and hard regime (Q3 : weak bonding strength and low power loss). Using this analogous technique, it was possible to fabricate the LT-CF bonded silicon solar cells with the various conditions displayed in Q3 of the quadrant plots, possessing the peeling strength of ~ 1N/mm and power loss of 2~3%.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.10a
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• pp.273-278
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• 1998

In this paper, basic micro-mechanical properties of unidirectional CFRP composite shell such as bonding strength, fiber volume fraction and void fraction are measured and tensile strength test is performed with a fixture. And then fracture surfaces are observed by SEM. In case of basic micro-mechanical properties, bonding strength is reduce with decreasing of radius of each ply in a shell for the effect of residual stress, fiber volume fraction is smaller than plate, and void fraction is vise versa. For these reason, tensile strength of shell is smaller than plate fabricated with same prepreg. For failure mode shell has many splitted part along its length, and it is assumed that this phenomenon is caused by the difference of bonding strength for residual stress.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.2
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• pp.87-93
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• 1997

The bonding strength evaluation of light weight materials for electrical vehicle applications has been performed through single lap joint tests in which the design parameters such as fillet, joint style, adherend, bonding overlap length,bonding thickness, and environmental condition(soaking time in $25^{\circ}C$ water) are considered. It is experimentally oberved that lap shear strength of joint increases for higher fillet height, longer overlap length, and thinner bonding layer thickness. Al-Al adherend combination shows much higher lap shear strength than AL-FRP and FRP-FRP adherend combinations. Riveting at adhesive bonded joint of AL-AL adherend combination makes lap shear strength decrease. Effect of soaking time on lap shear strength is negligible.