• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2000년도 춘계학술대회논문집
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• pp.187-191
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• 2000

High temperature creep behaviour of Al-5 wt% Mg alloy reinforced with 7.5% BN flakes was studied. The composite specimens showed two main creep characteristics : (1) the value of the apparent stress exponent of the composite was high and varied with applied stress (2) the apparent activation energy for creep was much larger than that for self-diffusion in aluminum The true stress exponent of the composite was set equal to 5. Temperature dependence of the threshold stress of the composite was very strong. Which could not be rationalized by allowing for the temperature dependence of the elastic modulus change. AIN particles which were incorporated into the Al matrix during fabrication of the composite by the PRIMEXTM method were found to be effective barriers to dislocation motion and to give rise the threshold stress during creep of the composite

• 한국세라믹학회지
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• 제48권2호
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• pp.147-151
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• 2011

In this study, we prepared graphene by using the modified Hummers-Offeman method and then introduced the metals (Pt, Pd and Fe) for dispersion on the surface of the graphene for synthesis of metal-graphene composites. The characterization of the prepared graphene and metal-graphene composites was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis and transmission electron microscopy (TEM). According to the results, it can be observed that the prepared graphene consists of thin stacked flakes of shapes having a well-defined multilayered structure at the edge. And the metal particles are dispersed uniformly on the surface of the graphene with an average particle size of 20 nm.

• 한국조리학회지
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• 제11권2호
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• pp.1-13
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• 2005

This study focused on the consumers' recognition of regional cuisine in Kyonggi province. Above all, the study was conducted being related to the tourism merchandising strategy based on the purposes of this study such as the establishment of concept of regional cuisine in Kyonggi province, its recognition and interest, and literature study was also conducted with empirical study. The results are as follows: First, to the question about whether they know the regional cuisine in Kyonggi province or not, 44% of respondents answered they don't know it well, which means recognition is very low. Second, to the question about the recognition of regional cuisine in Kyonggi province, Sujebi(a clear soup with wheat flakes in it) and Nengkonggugsu(iced bean noodles) of main dish, Samgyetang (chicken broth with ginseng and other ingredients) and Galbitang(beef-rib soup) of side dish, Moguachunghwachae(honeyed juice mixed with a Chinese quince as a punch) of drinks, and Kaedduck(a pie-shaped cake made of some rough flower) of desserts were highly recognized.

• 한국분말재료학회지
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• 제1권1호
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• pp.21-26
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• 1994

Aluminum was deposited on aluminum oxide powders using a fluidized bed reactor at atmospheric pressure. The aluminum oxide powders were irregular flakes with acute angles and the average particle size was 26 $\mu\textrm{m}$. The fluidized bed was formed by flowing argon gas at the velocity of 60 cm/sec. The optimal fluidization condition was obtained with the reactor designed to be tapered so that the fluid velocity decreases as the fluidizing gas goes up along the reactor. Aluminum was deposited by flowing TiBA(Triisobutylaluminum) evaporated at$250^{\circ}C$ through the fluidized bed reactor heated to 350~$450^{\circ}C$. The result from the analysis by XRD and EDAX confirmed the coating of aluminum and an SEM micrograph showed the conformality.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1999년도 제30회 추계학술대회
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• pp.57-61
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• 1999

The effect of the microstructure of gray cast iron on friction properties was investigated by using a pad-on-disk type friction tester. Cast iron samples used in this investigation were obtained from "step block" castings, which were designed to produce microstructure with different graphite flake morphologies from different cooling rate and solidification rate. Results of this work showed that the gray cast iron disks with long graphite flakes showed less fading. The rotors containing smaller amounts of ferrite showed higher friction coefficient and better fade resistance than others.an others.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2015년도 추계학술대회 논문집
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• pp.151-153
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• 2015

무전해도금법을 이용하여 Ag/Ni 코팅 Cu 플레이크를 제조한 후 Ni 코팅층의 P 함량에 따른 Ag dewtting 거동에 대한 연구를 수행하였다. Ni 코팅층 내 P 함량이 낮을수록 Ni 코팅층의 결정성 및 결정화 속도가 높아지는 것을 알 수 있었으며, 이는 Ni 코팅층 위에 형성된 Ag 코팅층의 dewetting 거동에 영향을 주는 것으로 분석되었다. 또한 격자 불일치도가 높을수록 잘 발생하는 dewetting 현상은 P 함량이 높아 결정성이 떨어지는 Ni 코팅층에서 더욱 빨리 일어남을 알 수 있었다.

• 한국주조공학회지
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• 제6권2호
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• pp.116-121
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• 1986

The effects of pressure during solidification on macro-and micro-structures have been studied in pure aluminium and Al-Si alloys. The application of pressure during solidifcation accelerated both equiaxed and columnar dendritic-growth due to stimulating of equiaxed survival and faster preferential growth of primary dendrites against the parallel direction of heat flow. Burden-Hunt model was modified to express the significant changes of CET behaviours under pressure. A further point to be noted was that greatly fine eutectic silicon flakes ($0.5\;{\times}\;13{\mu}m$) with the decrease of halo layers ($7{\mu}m$) of aluminium riched phases in the periphery of primary silicon particles were observed when pressure was applied during solidification.

• 대한전기학회논문지
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• 제41권6호
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• pp.640-651
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• 1992

This paper describes the electric properties of mica reinforced silicone composites with the parameter of curing condition of silicone resin, application amount of silane coupling agent to the mica paper and the mica wt% to the composite. Heat-resistant silicone resin and mica paper made of mica flakes are used to prepared the mica/silicone composite as matrix and filler, respectively. To improve the dielectric properties and interfacial adhesion between matrix and filler, silane coupling agent is applied on the mica paper. As for matrix, tan$\delta$ value of 30$0^{\circ}C$ heat-treated silicone resin is the lowest under 1%. The optimal wt% of coupling agent is 0.3% to the weight of mica paper. 80 wt% of mica as filler to the mica/silicone composite shows the best electric properties. And the mica reinforced silicone composite shows good high-frequency and mechanical tensile stress properties.

• Applied Microscopy
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• 제45권3호
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• pp.131-134
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• 2015

Here we show how by processing energy dispersive X-ray spectrometry (EDS) data obtained using highly sensitive, new generation EDS detectors in the AZtec LayerProbe software we can obtain data of sufficiently high quality to non-destructively measure the number of layers in two-dimensional (2D) $MoS_2$ and $MoS_2/WSe_2$ and thereby enable the characterization of working devices based on 2D materials. We compare the thickness measurements with EDS to results from atomic force microscopy measurements. We also show how we can use electron backscatter diffraction (EBSD) to address fabrication challenges of 2D materials. Results from EBSD analysis of individual flakes of exfoliated $MoS_2$ obtained using the Nordlys Nano detector are shown to aid a better understanding of the exfoliation process which is still widely used to produce 2D materials for research purposes.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.264.1-264.1
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• 2013

Graphene is a two-dimensional carbon material whose structure is one-atom-thick planar sheet of sp2-bonded carbon atoms densely packed in a honeycomb crystal lattice. It has drawn significant attention with its distinguished structural and electrical properties. Extremely high mobility and a tunable band gap make graphene potentially useful for innovative approaches to electronics. Although mechanical exfoliation of graphite and decomposition of SiC surfaces upon thermal treatment have been the main method for graphene, they have some limitations in quality and scalability of as-produced graphene films. Solutionphase and solvothermal syntheses of graphene achieved a major improvement for processing, however for device fabrication, a reproducible method such as chemical vapor deposition (CVD) growth yielding high quality films of controlled thickness is required. In this research, we synthesized hexagonal graphene flakes on Cu foils by CVD method and controlled its coverage, density and the size of graphene domains by changing reaction parameters. It is important to control these parameters of graphene growth during synthesis in order to achieve tunable properties and optimized device performance.