ZiRKON, KAOLiNiT, GiBSiT ve KOLEMANiT KARIŞIMINDAN MULLiT-ZiRKONYA KOMPOziTiN SENTEZi

Öz

Bu cahsmada, zirkon, gibsit, kaolinit ve kolemanit hammaddelerinin belirli orandaki kansirrundan reaksiyon sinterlemesi yolu ile mullit-zirkonya kompoziti sentezlenrnistir. Kansim, agrrhkca 25% zirkon, 25% kaolinit, 40% gibsit ve 10% kolemanitten meydana gelrnistir. XRD analizlerine gore, 1450°C'de mullit ve monoklinik zirkonya ana piklerin yarunda az miktarda parcalanmayan zirkon ve kalsiyum silikat piklerine ait izlere rastlanrrustir. Zirkon 1500°C'de tamamen parcalanmisur. I 550°C' de 12 saat sinterlenen kansirnla, 1500°C'de sinterlenen kansirrun XRD patemleri karsilastinldrgmda mullit ve monoklinik zirkonyamn ana pikJerine ait siddetlerindeki az bir farkla benzerlik gorulrnustur.

Anahtar Kelimeler

• Zirkon,Kaolinit,Gibsit,Kolemanit,Reaksiyon Sinterleme

SYNTHESIS OF MULLiTE-ziRCONiA COMPosiTE FROM ZiRCON, KAOLiNiTE, GiBBSiTE AND COLEMANiTE MiXTURES

Öz

In the present study, mullite-zirconia composite was synthesized by reaction sintering a mixture of zircon. kaolinite. gibbsite and colemanite raw materials. The mixture consisted of 25 wt.% zircon. 25 wt.% kaolinite. 40 wt.% gibbsite and 10 wt.% colemanite. The XRO analysis of the mixture sintered at 1450°C showed the mullite and monoclinic zirconia as the major phases along with zircon and calcium silicate as secondary phases with their trace amount. whereas zircon phase disappeared completely at 1500°C. With the difference in the intensity of mullite and monoclinic zirconia. the mixture sintered at 1550°C exhibit analogous XRD pattern compared with the mixture sintered at 15000C for 12 h.

Anahtar Kelimeler

• Zircon. Kaolinite
• Gibbsite
• Colernanlte
• Reaction Sintering

Kaynakça

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