• Journal of the Korean Ceramic Society
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• v.24 no.5
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• pp.411-416
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• 1987

Thermal expansions and thermal expansion coefficients of cordierite ceramics reinforced by SiC whiskers up to 40 vol. % were investigated. The composite specimens were hot pressed at 1523K for 30 min under 28.5 MPa pressing pressure in Ar atmosphere. Thermal expansions of the hot pressed composites were measured using a differential dilatometer up to 1262 K in air. Thermal expansions and thermal expansion coefficient of the composites increased with SiC whisker content. Thermal expansion behaviors of the composites were well explained by modelling parallel slabs randomly distributed on the whisker plane as the microstructural element of the composites.

• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.58.2-58
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• 2000

• Journal of Powder Materials
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• v.4 no.1
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• pp.48-54
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• 1997

NiAl powders containing oxide dispersoids have been produced by mechanical alloying process in a controlled atmosphere using high energy attrition mill. The powders have been consolidated by hot extrusion and hot pressing followed by isothermal annealing to induce microstructure coarsening to improve high temperature properties. Grain growth and dispersoid coarsening kinetics have been investigated as functions of annealing time and temperature. Coarsening of dispersion strengthen NiAl and dispersoid has been discussed. Some clues of secondary recrystallization have been investigated. Mechanical property measurements have been also made and correlated with the microstructures.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.232-233
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• 2002

Nanostructed high energy Nd-Fe-B based bulk magnet can be prepared by hot-working process (hot press and die-upset) from melt-spun amorphous or nanocrystalline powder.[1] Recently, we have investigated a modified method, current-applied pressure-assisted (CAPA) process, to produce nanocrystalline isotropic and anisotropic NdFeB magnets. The process consists of current-applied pressing the melt-spun powders to obtain isotropic precursor subsequent current-applied deforming the precursor to obtain textured magnet.[2-3] (omitted)

• Korean Journal of Materials Research
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• v.15 no.10
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• pp.667-670
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• 2005

Binary skutterudite $CoSb_3$ compounds were prepared by the arc melting and hot pressing processes and their thermoelectric properties were investigated in the range from 300 to 600 K. Annealing effect was correlated to phase transformation and homogenization. Thermoelectric properties of the arc-melted and hot-pressed $CoSb_3$ were discussed and compared. Undoped intrinsic $CoSb_3$ prepared by the arc melting showed p-type conduction, while it showed metallic behavior with increasing measuring temperature. However, hot pressed specimens showed n-type conduction, possibly due to Sb evaporation. Thermoelectric properties were remarkably improved by annealing In vacuum and they were closely related to phase transformation.

• Journal of Adhesion and Interface
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• v.7 no.3
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• pp.16-25
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• 2006

Water vapour permeable and water resistant film was laminated to made footwear woven fabric and non-woven fabrics by screen type with thermosetting reactive hot melt adhesive. Optimum conditions of each process were investigated, and the properties of film laminated fabric with optimum conditions are evaluated. The results are as follows. Thermosetting reactive polyurethane hot melt is retain proper heat resistance differently thermoplastic hot melt. Optimum melting adhesive process conditions are as follows ; drum temperature $95^{\circ}C$, hose temperature $97^{\circ}C$, feeding pipe temperature $100^{\circ}C$, screen temperature $105^{\circ}C$, pressure of opposite roller $1kgf/cm^2$, pressure of laminating roller $3kgf/cm^2$, finishing speed 15 m/min, melting temperature $120^{\circ}C$, cooling time 20 s, pressing temperature $130^{\circ}C$, pressing time 30 s. As the thickness of film was increased, the water vapour permeability was decreased but water resistance was increased, and the effect of film is dominant over all the others in the air permeability.

• Journal of the Korean Ceramic Society
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• v.39 no.2
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• pp.199-203
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• 2002

To investigate an effect of sintering atmosphere on microstructure and properties of metallic particle dispersed ceramic based composites, the powder mixtures of $Al_2O_3$/Fe-Ni, synthesized by chemical solution process, were hot-pressed under different atmospheres such as hydrogen or argon gas and different sintering temperature. Hot-pressed composite in a hydrogen atmosphere exhibited less reaction phase of $FeAl_2O_4$ and enhanced mechanical properties than that in an argon atmosphere. Furthermore, decreasing hot-pressing temperature produced a refinement of ceramic matrix and metallic dispersion particles as well as improvement of mechanical properties. The change of mechanical properties in the composites with different sintering conditions was explained by microstructural characteristics relating to reaction phase formation.

• Journal of the Korean Ceramic Society
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• v.25 no.4
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• pp.329-334
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• 1988

Kinetics of grain growth in PLZT ceramics during isothermal heat treatment and hot-pressing were investigated and the published data on grain growth were reanalyzed. It was found, in many cases, that the errors were introduced by ignoring the initial grain size. The grain growth of PLZT ceramics was confirmed to follow the parabolic normal growth : D2-Do2=Kt.

• Proceedings of the Materials Research Society of Korea Conference
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• 2001.05a
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• pp.57-57
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• 2001

• Proceedings of the Korean Ceranic Society Conference
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• 2000.04a
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• pp.70.2-70.2
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• 2000