• Proceedings of the Materials Research Society of Korea Conference
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• 2001.05a
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• pp.109-109
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• 2001

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.115.2-115
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• 2003

• Proceedings of the Materials Research Society of Korea Conference
• /
• 1994.05a
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• pp.39-40
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• 1994

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.153.1-153.1
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• 2007

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.10a
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• pp.228-231
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• 1997

A series of load relaxation tests was performed to determine stress-strain rate curves at high temperatures. Constitutive parameters of GBS and GMD were evaluated from the curves using the recently proposed inelastic deformation theory. Tensile tests and Microsturcture investigations showed deformation behavior as the relaxation test results predicted.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.38-39
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• 2002

일반적인 세라믹스 분말 합성방법으로서 고상법과 침전법 등은 성분 원소들간의 균일한 혼합이 어렵고, 대부분 최종 생성물의 합성 온도가 높아서 다성분계에 대하여 단일 상을 유지하면서 미세한 분말을 얻기가 힘들다. 그러나, 최근 들어 이러한 단점을 보완하기 위한 방법으로서 비정질 citrate법, 무기 금속염을 이용한 sol-gel법 등과 같이 비교적 공정이 단순하면서 입도 분포가 좁고 재현성이 우수한 구형의 초미립 또는 나노 분말의 제조에 적합한 방법들이 많이 연구되고 있다[1]. (중략)

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.114-115
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• 2002

다성분계 세라믹스에 대하여 초미립 및 나노 분말을 제조하기 위해 공침법, 비정질 citrate법, 무기 금속염을 이용한 sol-gel법, 분무 열분해법 등과 같이 비교적 단순한 공정이면서 입도 분포가 좁고 재현성이 우수한 구형의 초미립 또는 나노 분말의 제조에 적합한 방법들이 많이 연구되고있다[1-3]. 분무 열분해법은 출발물질로 용액을 사용하고 미세한 액적(droplet)을 초음파 분무 후 열분해 하여 분말을 합성하는 방법으로, 입자의 조성이 균질하고 구형의 형상을 갖는 우수한 결정상을 얻을 수 있다. (중략)

• Korean Journal of Materials Research
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• v.11 no.12
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• pp.1086-1090
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• 2001

Composition effects on microstructure and metallizing properties of the alumina sintered body were evaluated to develop the metallized alumina tubes having superior properties for electronic devices. SEM observation revealed that resultant micrographs and fractographs were varied with composition chance of additives and $SiO_2$-rich specimens showed better microstructural characteristics with uniform distribution of fine and round particles than other CaO-rich or MgO-rich ones. The resultant interfacial microstructure of the $SiO_2$-rich metallized alumina tubes also showed good metallizing properties with no defects between layers and uniform thickness of metallizing layer.

• Journal of the Korean Ceramic Society
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• v.31 no.2
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• pp.227-233
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• 1994

The Bi-Sr-Ca-Cu-O thin films were deposited by RF-magnetron sputtering method on Si(P-111) wafer without a buffer layer and annealed at various temperatures in oxygen atmosphere. The temperature dependence of electrical resistance, the microstructure of intermediate phase, and the surface morphology of films were examined by four probe method, XRD, and SEM, respectively. The chemical composition and the depth profile of the films were determined by ESCA spectra. Thin films annealed at $600^{\circ}C$ and $700^{\circ}C$ in oxygen atmosphere showed onset temperatures of 90 K and 85K, and Tc(zero) of 22K and 31K, respectively. The sample annealed at $700^{\circ}C$ had the highest volume fraction of superconducting phase and showed smooth microsturcture. In ESCA spectra, the thin films were homogeneous with depth.

• Journal of the Korean Ceramic Society
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• v.23 no.5
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• pp.61-66
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• 1986

The gas mixtures ($H_2$/$N_2$, He/$N_2$) having a high thermal conductivity allow the heat generated by the nitriding exotherm to be dissipated from the compact in to the nitriding atmosphere permitting a more accurate control of temperature and produces a more uniform microstructure. In order to observe the effect of the mixed gas atmosphere on the microsturcture of RBSN. the specimen was nitrided in the mixed gas atmosphere which was containe up to 50vol% $H_2$ or He for 0-12 hrs at 135$0^{\circ}C$. The addition of hydrogen to nitrogen gas resulted in the growth of a-needle at the early stage of nitrding increase of the reaction rate and a finer and more uniform microstructure. in case of the addition of helium the behaviour of reaction was similar to the one with pure nitrogen. As the amount of helium was increased a coarse microstructure was formed.