• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.1
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• pp.48-54
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• 2000

Influence of seed addition on the mullite synthesis was investigated from mixture powders of kaolin and aluminium trihydroxide which contain various $Al_2O_3$/SiO_2$ ratio (silica rich, stoichiometric, alumina rich). The flexural strength increases with the increase of the mullite-seed content in case of silica rich and stoichiometric mullite, but flexural strength decreases with the increase of the mullite-seed content in case of alumina rich mullite. Microstructural investigation revealed that aspect ratio of mullite grains increased with higher alumina content, along with lower sintered density. Mullite contents of specimens are increased with seed content regardless of $Al_2O_3$/SiO_2$ ratio of the mixture composition.

• Journal of the Korean Ceramic Society
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• v.35 no.8
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• pp.878-884
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• 1998

Synthesis of high purity mullite from korean resourceful kaolin and water-soluble aluminium salts was in-vestigated by addition of mullite seed. Single phase of mullite was formed at 1350$^{\circ}C$ however its mullite con-tent was 31-33% Maximum content of mullite synthesized from kaoin aluminium nitrate and 8wt% mul-lite seed was 98% at 1600$^{\circ}C$ for 4 hours.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.60.1-60
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• 2003

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.199.1-199
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• 2003

• Journal of the Korean Ceramic Society
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• v.38 no.2
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• pp.128-136
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• 2001

본 연구에서는 kaolin을 이용하여 반기상법, gel coating법, seed 첨가법으로 mullite를 합성하였으며 mullite 15 wt%를 고 알루미나질 내화물 원료에 첨가하여 내화물 시편을 제조하였다. 제조된 시편의 물성을 분석한 결과 seed 첨가법으로 제조된 mullite를 첨가한 시편의 물성이 338.60 MPa의 꺾임강도와 9,427 kgf/$\textrm{cm}^2$의 압축강도값을 나타내었다. 제조된 시편의 내화도 및 잔존선팽창수축률을 측정한 결과 나머지 두가지 방법으로 합성한 mullite나 일반적인 고 알루미나질 내화물에 비하여 좋은 특성을 나타내었다.

• Journal of the Korean Ceramic Society
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• v.38 no.2
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• pp.238-238
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• 2001

15% Syn M, sintered mullite(SM) and fused mullite(FM) was added to produce high alumina refractory materials. Mullite content of SM, FM and Syn M was 93.17%, 86.79%, 97.57% repectively. Mechanical properties of specimens (added 15wt% mullite) ware investigated to be flexural strength 338.60MPa, compressive stcngth 9,427kgf/㎠. But the specimen which imported mullite was added showed 5~10%l lower stregth than syn M added.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.198.1-198
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• 2003

• Journal of the Korean Ceramic Society
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• v.36 no.10
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• pp.1080-1086
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• 1999

Mullite/zirconia composite was synthesized by adding zirconia and Zircon to mixture of Hapcheon kaolin(grade pink A) and aluminium nitrate salt in order to enhance strength of the mullite specimens. Kaolin and aluminium nitrate salt was mixed milled and calcined at 100$0^{\circ}C$ and then 5wt% mullite seed was added to increase mullite content. The influence of the additives(ZrO2 and ZrSiO4) and sintering temperature on the strength of the sintered specimens was investigated. The flexural strength of the specimens containing 10wt% zirconia was enhanced from 150MPa without the additive up to 300MPa after heat treatment at 156$0^{\circ}C$ In the case of addition of 15wt% zircon the strength of the specimens systhesized at 1$600^{\circ}C$ was 225 MPa.

• Journal of the Korean Ceramic Society
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• v.38 no.3
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• pp.238-244
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• 2001

본 연구에서는 Seed 첨가법에 의하여 제조된 mullite(Syn M)와 외국산 mullite 2종류(sintered mullite : SM, fused mullite : FM)를 고알루미나질 내화물 원료에 적용하여 내화물 시편을 제조하였으며 mullite에 따른 결정상, 미세구조, 부피비중, 강도를 조사하였다. SM, FM, Syn M의 mullite 함유량은 93.17%, 86.79%, 97.57%이었으며 mullite를 15 wt% 첨가하여 제조한 시편의 물성을 조사한 결과 Syn M을 함유한 시편이 꺾임강도 338.60 MPa, 압축강도 9,427kgf/$\textrm{cm}^2$을 나타내었다. 외국산 mullite를 첨가한 시편의 강도는 Syn M을 첨가한 것보다 약 5~10% 정도 낮은 강도를 보였다.