In this study, the physical properties and fracture characteristics according to the tensile load are evaluated on the materials of the polymeric filler and carbon fiber-based composite sleeve technique. The polymeric filler and the composite sleeve technique are applied to areas where the pipe body thickness is reduced due to corrosion in large-diameter water pipes. First, the tensile strength of the polymeric filler was 161.48~240.43 kgf/cm2, and the tensile strength of the polyurea polymeric filler was relatively higher than that of the epoxy. However, the tensile strength of the polymeric filler is relatively very low compared to ductile cast iron pipes(4,300 kgf/cm2<) or steel pipes(4,100 kgf/cm2). Second, the tensile strength of glass fiber, which is mainly used in composite sleeves, is 3,887.0 kgf/cm2, and that of carbon fiber is up to 5,922.5 kgf/cm2. The tensile strengths of glass and carbon fiber are higher than ductile cast iron pipe or steel pipe. Third, when reinforcing the hemispherical simulated corrosion shape of the ductile cast iron pipe and the steel pipe with a polymeric filler, there was an effect of increasing the ultimate tensile load by 1.04 to 1.06 times, but the ultimate load was 37.7 to 53.7% compared to the ductile cast iron or steel specimen without corrosion damage. It was found that the effect on the reinforcement of the corrosion damaged part was insignificant. Fourth, the composite sleeve using carbon fiber showed an ultimate load of 1.10(0.61T, 1,821.0 kgf) and 1.02(0.60T, 2,290.7 kgf) times higher than the ductile cast iron pipe(1,657.83 kgf) and steel pipe(2,236.8 kgf), respectively. When using a composite sleeve such as fiber, the corrosion damage part of large-diameter water pipes can be reinforced with same level as the original pipe, and the supply stability can be secured through accident prevention.

As a filler metal for lowering the melting point of Ag, many alloy metal candidates have emerged, such as cadmium, with zinc, manganese, nickel, and titanium as active metals. However, since cadmium is known to be harmful to the human body, Cd-free filler metals are now mainly used. Still, no study has been conducted comparing the characteristics of joints prepared with and without cadmium. In addition, studies have yet to be conducted comparing the typical characteristics of brazing filler metals with special structures, and the joint characteristics of brazing filler metals with available frames. In this study, the characteristics of junctions of silver-based intercalation metals were compared based on the type of filler metal additives, using a special structure, a filler metal sandwich structure, to protect the internal base metal. The general filler metal was compared using the structure, and the thickness of the filler metal according to the thickness was reached. A comparison of the characteristics of the junction was conducted to identify the characteristics of an intersection of silver-based brazing filler metal and the effect on joint strength. Each filler metal’s collective tensile strength was measured, and the relationship between joint characteristics and tensile joint strength was explored. The junction was estimated through micro strength measurement, contact angle measurement with the base metal when the filler metal was melted, XRD image observation, composition analysis for each phase through SEM-EDS, and microstructure phase acquisition.

A Cu-15Ag-5P filler metal (BCuP-5) is fabricated on a Ag substrate using a high-velocity oxygen fuel (HVOF) thermal spray process, followed by post-heat treatment (300oC for 1 h and 400oC for 1 h) of the HVOF coating layers to control its microstructure and mechanical properties. Additionally, the microstructure and mechanical properties are evaluated according to the post-heat treatment conditions. The porosity of the heat-treated coating layers are significantly reduced to less than half those of the as-sprayed coating layer, and the pore shape changes to a spherical shape. The constituent phases of the coating layers are Cu, Ag, and Cu-Ag-Cu3P eutectic, which is identical to the initial powder feedstock. A more uniform microstructure is obtained as the heat-treatment temperature increases. The hardness of the coating layer is 154.6 Hv (as-sprayed), 161.2 Hv (300oC for 1 h), and 167.0 Hv (400oC for 1 h), which increases with increasing heat-treatment temperature, and is 2.35 times higher than that of the conventional cast alloy. As a result of the pull-out test, loss or separation of the coating layer rarely occurs in the heat-treated coating layer.

The electrochemical reaction between lead borate glass frit doped with Sn metal filler and Ni-Cr wire of a J-type resistor during a term of Joule heating is investigated. The fusing behavior in which the Ni-Cr wire is melted is not observed for the control group but measured for the Sn-doped specimen under 30 V and 500 mA. The Sn-doped lead borate glass frit shows a fusing property compared with other metal-doped specimens. Meanwhile, the redox reaction significantly contributes to the fusing behavior due to the release of free electrons of the metal toward the glass. The electrons derived from the glass, which used Joule heat to reach the melting point of Ni-Cr wire, increase with increasing corrosion rate at interface of metal/ glass. Finally, the confidence interval is 95 ± 1.959 %, and the adjusted regression coefficient, R in the optimal linear graph, is 0.93, reflecting 93% of the data and providing great potential for fusible resistor applications.

In aluminum brazing processes, corrosive flux, which is used in preventing oxidation, is currently raising environmental concerns because it generates many pollutants such as dioxin. The brazing process involving noncorrosive flux is known to encounter difficulties because the melting temperature of the flux is similar to that of the base material. In this study, a new brazing filler material is developed based on aluminum and non-corrosive flux composite powder. To minimize the interference of consolidation aluminum alloy powder by the flux, the flux is intentionally embedded in the aluminum alloy powder using a mechanical milling process. This study demonstrates that the morphology of the composite powder can be varied according to the mixing process, and this significantly affects the relative density and mechanical properties of the final filler samples.

In the present study, we develop a conductive copper/carbon nanomaterial additive and investigate the effects of the morphologies of the carbon nanomaterials on the conductivities of composites containing the additive. The conductive additive is prepared by mechanically milling copper powder with carbon nanomaterials, namely, multi-walled carbon nanotubes (MWCNTs) and/or few-layer graphene (FLG). During the milling process, the carbon nanomaterials are partially embedded in the surfaces of the copper powder, such that electrically conductive pathways are formed when the powder is used in an epoxy-based composite. The conductivities of the composites increase with the volume of the carbon nanomaterial. For a constant volume of carbon nanomaterial, the FLG is observed to provide more conducting pathways than the MWCNTs, although the optimum conductivity is obtained when a mixture of FLG and MWCNTs is used.

Prior to the design and production stages of the center pillar, the structural analysis must be carried out at the concept stage. Commercial softwares for the structural analysis provide benefits such as performance prediction and deformation. In this study, the structural analysis using SolidWorks was performed to investigate the stress and displacement characteristics of the center pillar for two types of collision positions and velocities. As the impact velocity increased, the maximum equivalent stress and displacement of the center pillar were larger. In the case of passenger cars, the equivalent stress and displacement according to the velocity change increased by about 133% and 116% at 16.5m/s , based on 5.5m/s . Also, the equivalent stress and displacement in the SUV car increased by about 119% and 378%, respectively

Prior to the experimental and production stages of the center pillar, a structural analysis must be carried out at the design stage. The commercial software for the structural analysis at the design stage provides benefits such as cost-effective and time economy. In this study, the structural analysis was performed to investigate the stress and displacement characteristics of the center pillar for five types of the applied loads using SolidWorks. The equivalent stress was relatively larger on the outside plate than the inside plate. The maximum equivalent stress according to the change of the applied loads increased linearly in the range of 47~181%. The deformation was larger at the upper end of the center pillar, and the maximum displacement was linearly increased in the range of 35~187%. The analysis results of the center pillar according to the applied loads show that the location and distribution of the maximum stress and displacement of the center pillar can be predicted.

Reflection properties, such as specular reflection and diffuse reflection, are very important optical properties for the reflector, which has high reflectance in the display and architecture industry. Calcite is lowcost, nontoxic, and stable over a wide temperature range. Therefore, it is one of the most widely using fillers in many industries and has some advantages over titania as a filler to improve reflectance. However, optical properties, especially those of ceramic-filled composites, have not been analyzed. We studied the reflectance of calcite composites with their surface roughness. The reflectance of the composites was determined using a UV-visible spectrometer. The surface morphology and the micro-structure of the composites were investigated by atomic force microscope. The reflectance of the composites was improved by increasing the content of calcite in the calcite-frit composite. The reflectance is related with the surface roughness in the composites. However, the reflectance depends on the calcite contents in materials with similar surface roughness.

국내 필러 시장은 2009년 189억 원에서 2014년 1,000억 원으로 연평균 약40% 성장한 것으로 예상된다. 최근 5년간 국내 필러 시장은 압도적인 성장세를 보여주고 있다. 구조적 성장 요인 이외에도 국내 시장의 고유한 특징이 있기 때문이다. 첫째 세계에서 가장 높은 인구당 피부 및 성형외과 의사 수, 둘째 유명 배우들을 통한 직접적인광고 전략으로 요약된다. 젊음과 아름다운 외모를 추구하는 트렌드가 지속되고 ‘쁘띠 성형’이라고 알려진 안면미용 시술에 대한 수요는 외모에 대한 관심 증가 및 안티에이징 시장 성장을 기반으로 폭발적으로 증가하고 있다. 본 연구에서는 첫째 더말 필러 브랜드 패키지디자인의 시각적 요소를 비교 분석하고 둘째 FGI와 심층인터뷰를 통해서 시각적 요소를 통한 선호도와 구매 영향 흐름을 파악하여 패키지디자인의 방향성을 제시한다. 그 결과 각 기업들의 패키지디자인에서의 차별성이 크지 않다는 것을 알 수 있었고 복잡하고 화려한 그래픽디자인 보다는 제품의 브랜드 로고 중심의 레이아웃을 선호하는 것을 알 수 있었다. 더말 필러 패키지디자인은 브랜드 이미지와 부합되는 디자인으로 지속적으로 나아가야하며 브랜드 컬러를 통한 브랜드, 제품별 특징을 더해주고 꾸준히 개발되어야 한다. 본 연구를 통해 도출한 브랜드 패키지디자인의 시각적 요소를 고려하여 추후 더말 필러 패키지디자인 개발 시 자사 브랜드 제품에 대한 구매를 유도할 수 있는 기초적 자료로 활용이 가능할 것이다.