• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.4
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• pp.481-488
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• 2018

This study suggest the improvement of the CFRP adhesive mixing ratio about acoustic window to enhance SONAR performance. The CFRP of submarine is produced by allocation an acoustic window zone by the beam width of SONAR sensors. During the sea trial, SONAR system's bearing and range accuracy data is not in tolerance due to debonding phenomenon on CFRP. The inappropriate mixing ratio of adhesives caused that peeling phenomenon occurred in the acoustic window part, which is the reason for the deterioration of SONAR sensors performance. The report includes explanation of test procedure of SONAR, root cause analysis, CFRP manufacturing procedure, laboratory tests results, and proof of the performance at the sea trial.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.209-212
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• 2006

Until now, sulfate attack is not completely understood. The purpose of this study is to provide a fundamental data to understand deterioration mechanism by sulfate attack. Chemical processes for products formed by sulfate attack were explained in this study. ASTM C1012 test and microstructural observations such as XRD and BSE analysis were carried out to manifest behavior and role of the products formed during sulfate attack. Regarding the dominant causes of sulfate attack, the main deterioration modes could be divided into 3 types; (1) expansive type, (2) onion-peeling type, and (3) acidic type.

• Journal of Biosystems Engineering
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• v.27 no.4
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• pp.301-310
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• 2002

With a purpose to manufacture an onion peeler, the root cutting equipment of the onion could be attached to a prototype onion peeler was developed. Before the experiment, the distribution of the dimensions of the Korean native onion were measured. And some types of the blades to cut and remove the root of the onion were designed and such characteristics as feasible revolution, conveying speed, and power requirement were investigated. From the result of the test, the selected one among the various cutters was the wing type blade with the round blade to cut out the root and with the vertical blade to cut a circular line. The optimum operating conditions of the wing type blade were revealed the revolution with no load was at 630 rpm, and the conveying speed was 0.08 m/s. Under these conditions, the maximum torque was 5.25 kg·m and the power requirement was 33 W, respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.509-512
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• 2006

In this study, the quality properties of recycled coarse aggregate, manufactured by the barcrusher, were compared to that of aggregate, manufactured by conservative systems. Test showed that recycled coarse aggregate, manufactured by the bar-crusher, had higher density and shape index, and exhibited lower absorption and abrasion ratios, compared with a con-crusher and an impact-crusher. This is due to the peeling-off effect of mortar, attached on recycled aggregate and the improved round shape of that.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.1
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• pp.81-89
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• 2022

It is necessary to increase the surface hardness and improve the wear resistance and peeling resistance through the surface treatment and performance evaluation of the mold steel. As a result of vacuum heat treatment analysis, residual austenite measurement and surface treatment wear test, retained austenite should be removed by sub-zero treatment, and retained austenite was completely removed by treatment at -196℃. The TiMon film coated on the sub-zero treated STD11 specimen showed the lowest coefficient of friction.

• Korean Journal of Materials Research
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• v.18 no.9
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• pp.486-491
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• 2008

The effect of annealing treatment conditions on the interfacial adhesion energy between electrolessplated Ni film and polyimide substrate was evaluated using a $180^{\circ}$ peel test. Measured peel strength values are $26.9{\pm}0.8,\;22.4{\pm}0.8,\;21.9{\pm}1.5,\;23.1{\pm}1.3,\;16.1{\pm}2.0\;and\;14.3{\pm}1.3g/mm$ for annealing treatment times during 0, 1, 3, 5, 10, and 20 hours, respectively, at $200^{\circ}C$ in ambient environment. XPS and AES analysis results on peeled surfaces clearly reveal that the peeling occurs cohesively inside polyimide. This implies a degradation of polyimide structure due to oxygen diffusion through interface between Ni and polyimide, which is also closely related to the decrease in the interfacial adhesion energy due to thermal treatment in ambient conditions.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.118-119
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• 2017

The combined waterproofing method is an excellent method to overcome the disadvantages of the single waterproofing method by composing two or more materials to complement each other, but it is a method that can cause defects such as separation and peeling between materials due to the heterogeneity of the applied two materials. In order to improve this, in this study, we aimed to develop a technology for inducing chemical unification between materials through a urea reaction with a coating material applied on the lower side by laminating a nonwoven fabric treated with a modified amine on the back surface of the sheet material, The adhesion performance test was carried out with the presence or absence of denatured amine treated nonwovens as variables. As a result of the test, it was confirmed that the adhesion performance of the specimen to which the modified amin - treated nonwoven fabric was applied was improved by about 60% or more as compared with the specimens not having the denatured amine treated specimen.

• Journal of Electrochemical Science and Technology
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• v.9 no.1
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• pp.9-19
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• 2018

The anodic behavior of aluminum (Al) foils with varying purity, capacitance, and withstand voltage in organic electrolytes was examined for EDLC. The results of cyclic voltammetry (CV) and chronoamperometry (CA) experiments showed that the electrochemical stability improves when Al foil has higher purity, lower capacitance, and higher withstand voltage. To improve the electrochemical stability of EDLC current collectors made of low-purity foil (99.4% Al foil), the foil was modified by chemical etching to reduce its capacitance to $60{\mu}F/cm^2$ and forming to have withstand a voltage of 3 Vf. EDLC cells using the modified Al foil as a current collector were made to 2.7 V with 360 F, and a constant voltage load test was subsequently performed for 2500 hours at high temperature under a rated voltage of 2.7 V. The reliability and stability of the EDLC cell improved when the modified Al foil was used as a current collector. To understand the deterioration process of the Al current collector, standard cells made of conventional Al foil under a constant voltage load test were disassembled, and the surface changes of the foil were measured every 500 hours. The Al foil became increasingly corroded, causing the adhesion between the AC coating layer and the Al foil to weaken, and it was confirmed that partial AC coating layer peeling occurred.

• Journal of the Korean Electrochemical Society
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• v.21 no.2
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• pp.28-38
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• 2018

Although the adhesion properties of composite electrodes are important for securing long-term reliability and realizing high energy density of lithium secondary batteries, related research has not been carried out extensively due to the limitation of measurement technology. However, surface and interfacial cutting analysis system(SAICAS), which can measure the adhesion properties while cutting and peeling a coating layer of $1{\sim}1000{\mu}m$ thickness, has been developed and applied for analyzing the adhesion properties of composite electrodes for lithium secondary batteries. Thus, this review presents not only the principle and measurement method of SAICAS but also comparison results between SAICAS and conventional peel test. In addition, application examples of SAICAS are introduced in the study of electrode design optimization, new binder derivation study, and binder distribution in composite electrode. This suggests that SAICAS is an analytical method that can be easily applied to investigate the adhesion properties of composite electrodes for lithium secondary batteries.

• Journal of Sensor Science and Technology
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• v.21 no.6
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• pp.395-401
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• 2012

The bond strength of three types of $TiO_2$ coatings onto fluorine-doped $SnO_2$ (FTO) glass was investigated with the aid of a tape test according to ASTM D 3359-95. Transmittance was then measured using an UV-vis spectrophotometer in the wavelength range of 300 nm to 800 nm to evaluate the extent of adhesion of $TiO_2$ nanorods/nanoparticles on FTO glass. A sharp interface between the coating layer and the substrate was observed for single $TiO_2$ coating ($TiO_2$ nanorods/FTO glass), which may be detrimental to the bonding strength. In multicoating sample ($TiO_2$ nanorod/$TiO_2$ nanoparticle/$TiO_2$ nanoparticle/FTO glass), the tape test was not performed due to severe peeling-off prior to the test. On the other hand, the dual coating sample ($TiO_2$ nanorod/$TiO_2$ nanoparticle/FTO glass) showed minimum variation of transmittance (4%) after the test, suggesting that the topcoat adheres well with the FTO substrate due to the presence of the $TiO_2$ nanoparticle buffer layer. The use of a $TiO_2$ nanorod electrode layer with good adhesion may be attributed to the excellent dye sensitized solar cell performance.