Isitini se-Silica

Isitini seSilica isitini esithunjiwe esakhiwa yi-mullite (3Al2O3.2SiO2) kanye ne-silicon carbide (SiC) njengezimbiwa eziyinhloko. Izici zayo akuzona nje ukumelana nokushisa okuphezulu kwe-mullite, kepha futhi nokumelana nokugqoka, ukumelana nokugqwala, kanye nokuqhuba okuhle kokushisa kwe-silicon carbide. Ngenkathi kwakhiwa iBaosteel ngawo-1980, izinto zokwakha ezazivela kwaNippon Steel, ezazibukeka njengamathangi e-torpedo, zazifana nezitini zamanje ezibunjiwe nge-silicon. Eqinisweni, kuyinto eguquliwe yemikhiqizo ye-aluminium silicate. Okwenziwe ekuqaleni kukalayini wensimbi yizitini eziyinjubaqa ezenziwe kakhulu nge-aluminium ephezulu. Ekuqhubekeni kobuchwepheshe kwemboni yensimbi nensimbi, ukuze kusheshiswe isivinini sokwenza insimbi, inani elithile leCalcium oxide (CaO) lidlula kulokho okubizwa ngokuthi yi-pretreatment. Ngale ndlela, okokuphikisa okuthangi kufanele kumelane nokugqwala okushisa okuphezulu kwensimbi encibilikile futhi kumelane nokugqwala okune-alkaline okuqinile. Ngokusobala, into ene-aluminium ephezulu ayikwazi ukumelana nayo, ngakho-ke ukufaka inani elifanele le-silicon carbide ezintweni eziphezulu ze-aluminium kwakha ukuhlukahluka okusha. Imboni ye-metallurgical iyibiza ngesitini esikhishwe nge-aluminium silicate esihlanganiswe ne-silicon carbide.

Ukusebenza kwesitini se-silicon carbide kuvela enqubeni yaso. Okokuqala, kubalulekile ukukhetha i-grade alumina ekhethekile ene-Al2O3 ephezulu kune-80% entweni eluhlaza. I-silicon carbide kufanele ihlanzeke futhi isidingo sobulukhuni se-Mohs siseduze no-9.5. Ukukhethwa kwenkampani ye-silicon carbide kuqinile kakhulu. Lolu hlobo lwamaminerali luyivelakancane ngokweqile. Iningi lemikhiqizo lisebenzisa i-SiO2 ne-C ukuhlanganisa i-SiC emazingeni aphezulu okushisa esithandweni sikagesi. Izinto zokusetshenziswa ezahlukahlukene zizokhiqiza umehluko wekhwalithi. Njengamanje, enqubeni yokukhiqiza ye-SiC, i-SiO2 entweni eluhlaza ivela kusilika wemvelo, kanti u-C ususelwa ku-coke yamalahle namalahle. I-Petroleum coke, ngokwemiphumela yethu yocwaningo, i-silicon carbide eyenziwe nge-petroleum coke ne-SiO2 inezinkomba eziphakeme ngobulukhuni nokuqina kokugqoka, futhi ilungele ukusetshenziswa njengezitini ze-silicon carbide. Izigaba eziyinhloko ze-crystal zezitini ezithunjiwe ezenziwe ngalezi zinto zokusetshenziswa yi-mullite, i-silicon carbide ne-corundum. Lawa amaminerali anokuqina okuphezulu, okubeka isisekelo semikhiqizo ekhanyayo eminyene futhi enamandla amakhulu.