• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.11a
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• pp.256-259
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• 2003

To develop cleaning process various particles should be deposited on wafer surfaces to measure particle removal efficiencies. The purpose of the article in to evaluate, removal efficient)r of silica and alumina particles from wafer surfaces when they are deposited by dry and wet method. Dry deposition in air and wet spray deposition using solutions are used. van der Waals are considered to calculate the adhesion force of particles on surfaces. Higher adhesion force is measured on alumina particles on silicon when particles are deposited in air.

• Tribology and Lubricants
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• v.35 no.1
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• pp.9-15
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• 2019

Graphene is a fascinating material for fabricating flexible and transparent devices owing to its thickness and mechanical properties. To utilize graphene as a core material for devices, the transfer process of graphene is an inevitable step. The transfer process can be classified into wet and dry methods depending on the surrounding environment. The adhesion between graphene and a target substrate determines the success or failure of the transfer process. As the surface energy of graphene is an important parameter that provides adhesion, it is useful to estimate the surface energy to understand the mechanisms of the transfer process. However, the exact surface energy of graphene is still disputed because the wetting transparency of graphene depends on the polarity of the liquid and target substrate. Previously reported results use graphene transferred by the wet method. However, there are few reports on the surface energy of graphene transferred by the dry method. In this study, the surface energy of graphene transferred by the wet and dry methods is estimated. Wetting transparency occurs for certain combinations of liquids and substrates. For graphene on a polar substrate, the surface energy decreases by 25 and 35% for the wet and dry transfer methods, respectively. However, the surface energy of graphene on dispersive substrates decreases by ~10% regardless of the transfer method. In conclusion, the surface energy of graphene is $36{\sim}38mJ/m^2$, and differs depending on the transfer method and polarity of the substrate.

• Journal of the Korea Computer Graphics Society
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• v.25 no.1
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• pp.1-11
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• 2019

More force must be applied when dragging a wet compared with a dry cloth lying on the table. Increased force is needed because the fluid between the cloth and the surface of the table produces an adhesion force. In this paper, we study the adhesion force between a wet cloth and the surface of an object. To compute the adhesion force, we used the adhesion force model used in textile research based on real-world experiments and also considered the effect of wrinkles, which, to our knowledge, has not been investigated in previous work. Furthermore, we studied the phenomenon in which a wet cloth adheres to the surface of an object and that in which a wet cloth adheres to itself when undergoing self-collision.

• Journal of Adhesion and Interface
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• v.10 no.2
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• pp.84-89
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• 2009

The objective of this research was to investigate the curing behavior and adhesion performance of urea-melamine-formaldehyde (UMF) resin for the four types of UMF-1, UMF-2, UMF-3, and UMF-4 which synthesized by the staged addition of melamine. Also, various network structures of these resin types were discussed based on their different curing behavior and adhesion performance. The curing behavior was evaluated by DMTA and thermal stability was checked by TGA. Adhesion performance was evaluated by dry and wet shear strengths and the pH value of each cured resin was checked to see its effect on the adhesion performance. The results indicated that the UMF-1 resin type by the addition of melamine initially with the urea and formaldehyde at the same F/(U+M) rate showed the lowest thermal stability, rigidity (${\Delta}E^{\prime}$), temperature of tan ${\delta}$ maximum ($T_{tan}\;_{\delta}$), and wet shear strength, and pH value of cured resin. In wet shear strength, however, the UMF-4 resin type appears to be slightly higher than UMF-1 resin type.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.517-518
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• 2012

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.501-504
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• 2006

Recycled aggregate mortar contains plenty of calcium hydroxide to improve the strength of blast furnace slag, although the surface mortar made of recycled aggregate deteriorates adhesion to cement paste and blast furnace slag has a low initial strength. Therefore, this study assumes that the combination with both recycled aggregate and blast furnace slag will produce a better performance. The results of the experiment show that dry mortar made of recycled aggregate provides with higher strength than wet mortar does at the 3-day and 7-day age, while lower at the 28-day age. It indicates that a large amount of cement mortar made of dry recycled aggregate has deteriorated adhesion strength. The mixes with 30% and 50% of blast furnace slag and 50% and 75% of recycled aggregate provide with much better strength at the 7-day age, although they usually have latent hydraulic property at the 28-day age. It indicates that calcium hydroxide($Ca(OH){_2}$) in recycled aggregate has affected ground granulated blast furnace slag.

• Journal of Adhesion and Interface
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• v.17 no.3
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• pp.89-95
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• 2016

An environmentally friendly water-based pressure sensitive adhesive (PSA) was designed in an attempt to replace the solvent-based adhesive for dry lamination used in flexible food packaging films. Instead of using a low molecular weight surfactant, which may have variable material properties, a high molecular weight dispersant was used for emulsification. A polymeric nano-dispersant (PND) was synthesized using solution polymerization, and it was used as a micelle seed in the surfactant, resulting in the synthesis of a core/shell grafted acrylic adhesive. The shell and core exhibited different $T_g$ values, so that the initial adhesion strength and holding power were complemented by the film's flexibility, which is required to provide good adhesion of thin films. Results showed that the PSA designed in this study using the PND instead of traditional low molecular weight surfactant had adhesive properties applicable to the flexible packaging with appropriate tack.

• Journal of Powder Materials
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• v.25 no.6
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• pp.501-506
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• 2018

With the recent remarkable improvements in the average speeds of contemporary trains, a necessity has arisen for the development of new friction modifiers to improve adhesion characteristics at the wheel-rail interface. The friction modifier must be designed to reduce slippage or sliding of the trains' wheels on the rails under conditions of rapid acceleration or braking without excessive rolling contact wear. In this study, a novel composite material consisting of metal, ceramic, and polymer is proposed as a friction modifier to improve adhesion between wheels and rails. A blend of Al-6Cu-0.5Mg metallic powder, $Al_2O_3$ ceramic powder, and Bakelite-based polymer in various weight-fractions is hot-pressed at $150^{\circ}C$ to form a bulk composite material. Variation in the adhesion coefficient is evaluated using a high-speed wheel-rail friction tester, with and without application of the composite friction modifier, under both dry and wet conditions. The effect of varying the weighting fractions of metal and ceramic friction powders is detailed in the paper.

• Journal of the Korean institute of surface engineering
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• v.50 no.5
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• pp.373-379
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• 2017

Dry processes like evaporation and sputtering in vacuum chamber are difficult to make a uniform, large area and high quality film on thin PET substrate because of PET degradation and bad adhesion. On the other hand, wet processes like electro or electroless plating have complex processes and require high environmental cost. In this study, we successfully prepared $2{\mu}m$ Zn/Cu/Ni multilayers coated on $12{\mu}m$ polyethylene terephthalate (PET) substrate by using dry-wet mixing processes. Their surface electric resistances were evaluated around $0.2{\Omega}$ by using 4 probe measurements. Furthermore, their corrosion resistance also evaluated by natural potential test and compared with other wet, dry and mixing process samples.

• Journal of the Korean Wood Science and Technology
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• v.12 no.2
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• pp.35-43
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• 1984

This study was carried out to investigate the block shear strength of the 2ply laminated wood composed of Pinus thunbergii with ureaformaldehyde resin as adhesives according to pressure (6, 9, 12, 15kg/$cm^2$), pressing time(5, 10, 20, 30 hrs.), amount of spread(54, 108, 217, 324g/$cm^2$), hardener(10, 20, 30, 40% of 10% $NH_4CL$ on resin) and extender(0, 5, 10, 15% wheat flour on resin), and the bending strength and bending young's modulus of laminated beam according to the number of ply. The results were summarized as follows; 1. According to pressing pressure with amount of spread 217g/$cm^2$ both dry and wet shear strength of laminated wood showed the highest in 15kg/$cm^2$, and hot-cold soaking treatment showed the highest in 9kg/$cm^2$, while all shear strength of dry, wet and hot-cold soaked laminated wood have been reduced with the increasing of pressing time. 2. According to amount of spread, adhesion strength with the dry, wet and hot-cold soaking treatments revealed the highest in 217g/$cm^2$ and have been reduced under or over 217g/$cm^2$ of spread. 3. According to addition of hardener and extender, all shear strength of laminated block with the dry, wet and hot-cold soaking treatments have been reduced in increasing of addition amount of hardener and extender. The bending strength of beam according to the number of ply showed the highest in 2ply laminated wood and horizontal loading beam to glue line had the higher in strength than the vertical loading.