• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.6
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• pp.98-106
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• 2022

Among the parts assembled in the gas receiver of a marine engine, the titanium alloy stainless steel (STS 316Ti) wire mesh serving as a filter was broken, and the related part, the turbine fan of the turbocharger, was damaged. In this study, a sample of the grid wire mesh was collected and the cause of breakage was analyzed, and a method of minimizing the dent mark caused by the mold during wire forming, which is one of the most direct causes, was studied. In addition, the optimum mold shape was realized through FEM simulation, and the wire wave molding machine capable of controlling the speed was improved by supplementing the problems of the existing wire wave molding machine, thereby improving durability with minimal dent marks.

• Journal of Technologic Dentistry
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• v.28 no.1
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• pp.9-17
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• 2006

The purpose of this study was to evaluate the titanium castability with a spin type casting machine(TiCast, Super R, Selec, Osaka. Japan). We tested phosphate bonded investment "Rematitan$^{(R)}$Plus(Dentaurum, Inc., Pforzheim, Germany)"of mesh grid pattern and plate pattern. Four different mold temperatures(room temperature, 200$^{\circ}C$, 400$^{\circ}C$ and 600$^{\circ}C$) were prepared for the present study. In mesh grid pattern with spruing of $\varphi$0.88㎜ dimeter, when the mold temperature increased, high percentage of castability was gained. Mold temperature showed a highly significant(p<0.05) correlation on the castability, In plate pattern, the higher the mold temperature during casting, the greater the adhesive phenomenon between Ti surface and the investment.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.4 s.33
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• pp.55-59
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• 2004

We fabricates the $TiO_2$ thin film from anatase phase $TiO_2$ powder having good photocatalytic property using aerosol deposition method at room temperature. Aerosol deposition method, which sprays an aerosol powder with ultrasonic velocity and deposits a thin film on substrate at low temperature, has the advantages of low thermal stress and low cost. To fabricate the $TiO_2$ thin film, the aerosol bath pressure and chamber pressure were 500 torr and 0.4 torr, respectively. The difference of aerosol bath pressure and chamber pressure accelerated the $TiO_2$ nano powder to ultrasonic velocity through the nozzle of $0.4 mm{\times}10 mm$ and $TiO_2$ thin film was finally formed. SS mesh with diameter of 50 mm was used as a substrate to apply the $TiO_2$ thin film to water quality purification. The raw powder was dehydrated for the good dispersion of $TiO_2$ powder. To suppress the formation of second particle, the powder was dispersed for 90 min in alcohol bath by ultrasonic treatment and desiccated. The grain size of $1 {\mu}m$ was observed in $TiO_2$ thin film deposited on SUS mesh by scanning electron microscopy (SEM). The anatase phase of $TiO_2$ thin film was also observed by X-ray diffraction (XRD) and the anatase phase of raw powder was nicely maintained after aerosol deposition. The results are applicable to water treatment filter having photocatalytic reaction.

• Journal of Korean Society on Water Environment
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• v.28 no.2
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• pp.219-223
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• 2012

The fixed solid catalysts such as glass bead, steel mesh, and $TiO_2$ coated ceramic bead were used to investigate effect of radical production at different frequencies. The radical production rate at 300 kHz was faster than that at 35 kHz without solid, but the tendency was changed with the presence of glass bead. The presence of glass beads create non-continuous points between the solid and liquid phases leading to increased formation of cavitation bubbles. However, the radical production decreased when steel mesh was used at 35 kHz although the surface area of contact with liquid was same when glass bead was used. Hence the solid catalyst did not always enhance the radical production. The radical production using $TiO_2$ coated ceramic bead was dramatically increased at 35 kHz due to the breakage of $TiO_2$ coated ceramic bead. Therefore the radical productions at 300 kHz using fixed solid catalysts generally increased while at 35 kHz the results fluctuated according to the experimental conditions.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.157-171
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• 1997

This study was conducted to see the effect of TiN ion-plating on the bond strength of orthodontic bracket. Three stainless-steel brackets with different base types were chosen; when TiN ion-plated brackets and non iorrplated brackets were bonded to the teeth, initial and long-term bond strength were measured, The observations oi bonding surface and failure sites through the scanning electron microscope were analysed and compared. The summary of this study was as follows; ${\cdot}$ When TiN ion-plating was not applied, the Micro-Loc type was the highest in bond strength atter 24 hours as $5.89{\pm}1.77$ MPa, followed by $4,27{\pm}1.12MPa$ for Foil Mesh type and $2.64{\pm}0.58MPa$ for Undercut type(P<0.05). ${\cdot}$ Under TiN ion-plating, the bond strength after 24 hours showed: Micro-Loc type $-6.26{\pm}1.51MPa$, Foil Mesh type $-7.45{\pm}2.01MPa$, Undercut type $-2.93{\pm}0.84MPa$. Unlike in the case of non ion-plating, Foil Mesh type showed a higher strength than Micro-Loc type, with Undercut type still showing the lowest bond strength(P<0.05). The bond strength, after 24 hours, increased in case of ion-plated in all 3 types, but a significant increase was shown only in Foil Mesh type(P<0.001). ${\cdot}$ Under a long-term immersion, regardless of ion or non ion-plating, bond strength in general increased over the initial bond strength(one day), with more stability. ${\cdot}$ Through scanning electron microscopic observation of bonding surface, it was found that, regardless of the bracket base type or the application of ion-plating, the resin was thoroughly spreaded into bracket base to form a solid bonding surface between the bracket and the tooth. This was also true in case of a long-term immersion. ${\cdot}$ The scanning electron microscopic observation of failure sites revealed diverse failure patterns.

• Transactions of the Korean hydrogen and new energy society
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• v.18 no.4
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• pp.452-457
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• 2007

Titanium foil and mesh(anodized tubular $TiO_2$ electrode, ATTE) were anodized in a bath at $5^{\circ}C$ with 20V external bias applied, then annealed at different temperatures($450^{\circ}C{\sim}850^{\circ}C$) to obtain tubular $TiO_2$ on the Ti substrate. The prepared sample was used to investigate rate of hydrogen production as well as Cr(VI) reduction. The ATTEs annealed at relatively lower temperatures showed higher activity than those at relatively higher temperatures. In particular, the Cr(VI) reduction was pH-dependent. To improve photocatalytic Cr(VI) reduction with the ATTEs, two configurations, fixing foil type and rotating mesh type, were also compared. As a result, the rotating mesh type was much more effective for Cr(VI) reaction than the former due to the more efficient use of the light. In the rotating type reactor, as the rotating speed increased, the rate of the Cr(VI) reduction was getting faster.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1338-1347
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• 2018

In this study, Ti-mesh based electrodes were fabricated for the application of anode to the electrolysis process for wastewater treatment using Pd electroless plating method. The removal performance of the prepared Pd / Ti-mesh electrode was evaluated as representative dye RO16, and the durability and performance were maximized by varying the electrode manufacturing conditions. As a result, it was confirmed that the coating condition had no significant effect on the performance, and that the heat treatment process greatly affected the performance and the durability was improved. In addition, we tried to maximize performance and durability by complexing Ir, Ru, and Ta. However, as the thickness of the layer increased due to the limitation of the coating method, the resistance increased and the performance decreased accordingly.

• Journal of Powder Materials
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• v.17 no.5
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• pp.365-372
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• 2010

The evolution of sinterability, microstructure and mechanical properties for the spark plasma sintered(SPS) Ti from commercial pure titanium(CP-Ti) was studied. The densification of titanium with 200 mesh and 400 mesh pass powder was achieved by SPS at $750{\sim}1100^{\circ}C$ under 10 MPa pressure and the flowing $H_2$+Ar mixed gas atmosphere. The microstructure of Ti sintered up to $800^{\circ}C$ consisted of equiaxed grains. In contrast, the growth of large elongated grains was shown in sintered bodies at $900^{\circ}C$ with the 400 mesh pass powder and the lamella grains microstructure had been developed by increasing sintering temperature. The Vickers hardness of 240~270 HV and biaxial strength of 320~340 MPa were found for the specimen prepared at $950^{\circ}C$.

• Journal of the Korean institute of surface engineering
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• v.49 no.6
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• pp.575-579
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• 2016

The metal mesh films with thickness of 1.0, 1.5, $2.0{\mu}m$ were prepared by photolithography using Ag, Al, and Cu metals. Every metal films were showed C(111) preferred orientation and Ag showed the lowest resistivity and followed by Al and Cu. The transmittance of almost films were higher than 90%. But, the Ag film with thickness of $2.0{\mu}m$ was delaminated during photolithography process due to low adhesion. So, Cu and Ti metal films were introduced under Ag film to improve adhesion property. The Cu film showed higher adhesion properties compared to Ti film. Furthermore, the Ti films that deposited on Ag film showed higher acid resistance.

• Korean Journal of Materials Research
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• v.9 no.6
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• pp.577-582
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• 1999

In order to make the electroconductive $Si_3N_4$-TiN composities, the Si-Ti(N) compacts were nitrided at $1450^{\circ}C$ for 20hours, and then they were post-sintered by a gas-pressure-sintering technique at 1TEX>$1950^{\circ}C$ for 3.5 hours. As starting powders, commercial si powder of about $10\mu\textrm{m}$, two types of Ti powders of 100 and 325 mesh, and fine-sized TiN of $2.5\mu\textrm{m}$ powders were used. In the $Si_3N_4$-TiN sintered bodies used Ti powders, the relative density and fracture strength and electrical conductivity are low due to the existence of large amounts of coarse pores. However, in the $Si_3N_4$-TiN composite used TiN powder, the fracture toughness, fracture strength and electrical resistivity were $5.0MPa{\cdot}m^{1/2}$, 624MPa and $1400{\omega}cm$, respectively. The dispersion of TiN particles in the composite inhibited the growth of $Si_3N_4$ in the shape of rod and made strong strain field contrasts at the $Si_3N_4$-TiNinterfaces. It was recognized that microstructural control is required to improve the electrical conductivity and mechanical properties of $Si_3N_4$-TiN composites by dispersing TiN particles homogeneously.