• Journal of the Korean Magnetics Society
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• v.16 no.1
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• pp.98-101
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• 2006

Electron transport properties of nanostructured Pb thin film, consisting of grains, have been studied. Nanostructured thin films were fabricated on a substrate held at low temperature and their thicknesses were less than 10nm. While temperature of the film increased from 1.3 K to room temperature, the change in normal state sheet resistance has been measured. As the annealing temperature varies, the normal state sheet resistance shows a non-monotonic and irreversible change. Such behavior can be understood with the Pb grain growth due to annealing of the film.

• Journal of the Korean Vacuum Society
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• v.3 no.1
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• pp.45-50
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• 1994

CoCr 박막에 있어서 C축 결정배향성과 미세구조 변화에 대한 Co73Cr27 씨앗층의 영향이 조사되 었다. 기록밀도가 높고 재생전압도 높은 CoCr 수직기록매체를 개발하기 위해서는 CoCr층의 두께가 엷 으면서 결정배향성이 우수하고 결정립 크기가 적고 균일한 자성기록막 제조가 필요하다. CoCr 단층막 또는 CoCr/퍼말로이 이중막 제조에서 500$\AA$정도의 Co73Cr27 층을 씨앗층으로 만들어 줌으러써 기록층인 CoCr 박막이 $0.2mu$m의 두께에서도 천이층이 거의 없고 결정배향성이 우수한 자성막을 제조할 수 있었 다. 또한 Co73Cr27 씨앗층은 비록 결정립 크기는 증가시켰지만 기록층의 에피택시 성장에 보다 바람직 한 것으로 조사되었다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.8
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• pp.1175-1187
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• 1997

Densification behavior and grain growth of zirconia powder compacts are investigated under high temperature. Experimental data are obtained for zirconia powder under pressureless sintering, sinter forging and hot isostatic pressing. The constitutive equations by Kwon et al. are used for diffusional creep and grain growth. The constitutive equations by McMeeking and co-workers are also included to study the effect of power-law creep. These constitutive equations are implemented into a finite element program (ABAQUS) to investigate the friction effect during sinter forging and the canning effect during hot isostatic pressing. The agreements between experimental data and finite element results are very good in pressureless sintering and hot isostatic pressing, but not as good in sinter forging.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.11
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• pp.2749-2761
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• 2000

Densification, grain growth, and phase transformation of nanocrystalline ceramic powder were investigated under pressureless sintering, sinter forging, and hot pressing. A constitutive model for densification of nanocrystalline ceramic powder was proposed and implemented into a finite element program (ABAQUS). A grain growth model was also proposed by including the effect of applied stress on grain growth when phase transformation occurs. Finite element results by using the proposed models well predicted densification behavior, deformation, and grain growth of nanocrystalline titania powder during pressureless sintering, sinter forging, and hot pressing. Finite element results by using the proposed model also well predicted experimental data in the literature for densification behavior of nanocrystalline zirconia powder during pressureless sintering and sinter forging.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.363-368
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• 2000

Densification, grain growth, and phase transformation of nanocrystalline ceramic powder were investigated under pressureless sintering, sinter forging, and hot pressing. A constitutive model for densification of nanocrystalline ceramic powder was proposed and implemented into a finite element program (ABAQUS). A grain growth model was also proposed by including the effect of applied stress on grain growth when phase transformation occurs. Finite element results by using the proposed models well predicted densification behavior, deformation, and grain growth of nanocrystalline titania powder during pressureless sintering, sinter forging, and hot pressing.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.2
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• pp.152-158
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• 2000

The crystallographic grain orientation of {{{{ { ZrB}_{2 } }}}}-ZrC composite sintered by pressureless a sintering(PLS) and spark plasma sintering (SPS) was analysed by the SEM-EBSP technique. In the case of PLS, (160) plane of {{{{ { ZrB}_{2 } }}}} was oriented to ND direction, (101) and (111) plane of ZrC were oriented to ND direction. In the case of SPS, (0001) plane of {{{{ { ZrB}_{2 } }}}} was strongly oriented to ND direction. Only (001) plane of ZrC was oriented to ND direction. The PLS specimen had weakly oriented grain structure and interface between {{{{ { ZrB}_{2 } }}}} and ZrC was found to be more stable than that of SPS but the SPS specimen had a preferentially oriented grain structure.

• Korean Journal of Materials Research
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• v.4 no.5
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• pp.581-589
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• 1994

Magnetic properties and microstructures of the $Co_{83}Cr_{17}$ films growing under the applied magnetic field were studied. In comparison, those of the films growing without magnetic field were also studied. Magnetic field does not affect saturation magnetization and in-plane coercivity of the films. On the contrary perpendicular coercivity and effective perpendicular anisotropy field decreased. Grain size and the thickness of the so-called transition layer were not affected and the C-axis alignment of the films was slightly deteriorated due to magnetic field. Also, microstructures of the sputtered films showed larger grain sizes of strong (002) preferred orientation for thicker film specimens independent of applied magnetic field.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.62-62
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• 2002

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.1061-1062
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• 2004

• Proceedings of the Korean Nuclear Society Conference
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• 2003.05a
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• pp.223.2-223.2
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• 2003