Izitena zeMagnesia alumina spinel

Izitena zeMagnesia alumina spinel zisebenzisa i-magnesia yezitena zaseprayimari kunye ne-sintered magnesia alumina spinel sand ngomlinganiselo we-C / S we-0.4 njengezinto ezingafunekiyo, ezinobungakanani obubalulekileyo be-3mm. Ubungakanani bamasuntswana e-magnesia amkela amasuntswana ama-3 ~ 1mm amakhulu, <1mm amasuntswana aphakathi kunye <0.088mm umgubo ocoliweyo njengezithako zenqanaba ezintathu. Sebenzisa inkunkuma ye-sulpite inkunkuma njenge-arhente yokubopha, xuba kunye nokusila okumanzi, kunye nokumila ngo-300t wokucinezelwa kwezitena. Emva kokuba umzimba oluhlaza womile, uyadutyulwa nge-1560 ~ 1590 ° C. Umoya obuthathaka we-oxidizing kufuneka ulawulwe ngexesha lokudubula.

Iimpawu ezinobushushu obuphezulu kunye noxinzelelo lokuqina kwezitena ze-periclase-spinel zingcono kunezo zitena ziqhelekileyo ze-magnesia alumina. Amandla oxineneyo kwiqondo lobushushu begumbi yi-70-100MPa, kunye nozinzo lokothusa lwe-thermal (1000 ℃, ukupholisa amanzi) ngamaxesha angama-14-19. Izitena ze-periclase-spinel zingasetyenziselwa kwindawo enobushushu obuphezulu bee-kilns ezijikelezayo zekalika kunye nee-kilns ezijikelezayo zesamente.

Ilizwe lam le-magnesium-aluminium spinel yamkela iinkqubo ezimbini zemveliso: ukuntywila kunye nokuhlangana. Izinto ezingavunyelwanga ikakhulu i-magnesite kunye ne-alumina powder okanye i-bauxite. Ngokwezibonakalisi ezahlukeneyo ze-magnesia kunye ne-alumina, i-magnesia-rich spinel kunye ne-aluminium-rich spinel zihlelwa kwaye zisetyenziswa kwiindawo ezahlukeneyo.

1. Ngokwenkqubo yemveliso okanye indlela: sintered magnesium aluminium spinel (sintered spinel) kunye nefused aluminium magnesium spinel (fused spinel).

2. Ngokwemveliso ekrwada, inokwahlulahlulwa ibe: yi-bauxite-based magnesia-aluminium spinel kunye ne-alumina-based magnesia-aluminium spinel. (Ukucoca okanye ukudibanisa)

3. Ngokomxholo kunye nokusebenza, kwahlulwe kwaba: isipelingi esine-magnesium, ispinel esine-aluminium kunye ne-spinel esebenzayo.

Isitena seMagnesia alumina spinel sikwabizwa ngokuba yitena ye-periclase-spinel, eyenziwe ngobunyulu obuphezulu obufakelweyo ubucoceko okanye ubunyulu obunemigangatho emibini yokulinganisa i-magnesia kunye nokucoceka okuphezulu okwenziwe kwangaphambili kwe-magnesia-aluminium spinel njengezona zinto ziphambili, kusetyenziswa izithako ezichanekileyo Forming Inkqubo yoxinzelelo oluphezulu kunye noxinzelelo oluphezulu lokudubula. Xa kuthelekiswa nezitena zemagnesia-chromium, le magnesia-aluminium edityanisiweyo yezitena ayiphelisi kuphela ingozi ye-hexavalent chromium, kodwa ikwanokuxhathisa umhlwa, ukumelana nokuncitshiswa kwe-oxidation, ukumelana nobushushu kunye nokuqina kobushushu obuphezulu. Isamente enkulu kwaye iphakathi ngokomgangatho Eyona nto ifanelekileyo ye-chromium-free refractory yendawo yotshintsho lwesithando somlilo. Isetyenziswe nakwizixhobo ezinobushushu obuphezulu ezinje ngeeililns zekalika, iiglasi, kunye nezixhobo zokucoca ngaphandle kweziko, kwaye ikwafumene iziphumo ezilungileyo.

Izalathiso ezibonakalayo nezemichiza zezitena zemagniziyam-aluminiyam ezijikelezayo zezitena zezi: MgO 82.90%, Al2O3 13.76%, SiO2 1.60%, Fe2O3 0.80%, ebonakalayo porosity 16.68%, density mass 2.97g / cm3, temperature standard compressive strength 54.4MPa, I-1400, amandla e-flexural 6.0MPa.

Izitena zeMagnesium-aluminium spinel zisetyenziswe ngempumelelo kummandla wotshintsho wesamente, kodwa ziyathanda ukwamkelwa nokwakheka kwesakhiwo xa zisetyenziswa kwindawo yokudubula, kunzima ukuxhoma kulusu lweziko, kunye nokunganyangeki kakuhle kumphunga wealkali. kunye nesamente yokuncamathela kwinqanaba lolwelo. Kwaye amandla amabi okuxhathisa uxinzelelo loomatshini olubangelwa kukuguqulwa komzimba weziko lokunciphisa isicelo kummandla wokudubula. Ngesi sizathu, abaphandi baphuhlise i-magnesia-aluminium spinel yezitena eziguqulweyo ezifanelekileyo kwindawo yokudubula yeesilina ezijikelezayo. Ngexesha lokudubula kunye nokusetyenziswa, inxenye ye-Fe2 + kulwakhiwo lwe-periclase-spinel eyilahleko i-oxidized to Fe3 +. Emva koko, icandelo le-Fe2 + kunye ne-Fe3 + kwi-iron-aluminium spinel eyahlukileyo kwi-periclase matrix ukwenza i-MgOss. Kwangelo xesha, ezinye i-Mg2 + kwi-matrix nayo iyahluka kwi-iron-aluminium spinel amasuntswana, kwaye isabela kunye ne-Al2O3 eseleyo ukusuka ekuboliseni kwesinyithi-i-aluminium spinel ukwenza i-magnesium-aluminium spinel. Olu luhlu lwempendulo lukhatshwa kukwandiswa kwevolumu, ekhokelela ekwenziweni kwee-microcracks. Ukuya

Izitena ze-iron-aluminium spinel zineepropathi ezintle zokuxhoma eziko kunye nokuxhathisa kukothuka. Phakathi kwabo, isizathu sokuba i-iron aluminium spinel ixhomeke kakuhle kulusu lweziko iyafana naleyo yezitena ze-mafic-iron spinel. Kwakhona kungenxa yesenzo se-CaO kwi-clinker yesamente kunye ne-Fe2O3 eqinileyo echithwe kwi-periclase ukwenza iikristali ezinokumanzisa i-periclase. , I-calcium ferrite edibanisa i-bond kunye ne-firebrick kunye. Isizathu sokuchasana okuhle kotshiso olushushu kukuyilwa kwee-microcracks.

Kwinkqubo ye-MgO-Al2O3, isisombululo esiqinileyo se-Al2O3 kwi-periclase kwi-1600 ° C imalunga ne-0; isisombululo esiqinileyo kwi-1800 ° C yi-5% kuphela, encinci kakhulu kune-Cr2O3. Kwinkqubo ye-MgO-Al2O3, ekuphela kwengqokelela yebhanari yi-magnesium aluminium spinel. Indawo yokunyibilika ye-magnesium aluminium spinel iphezulu njenge-2135 ℃, kwaye elonaqondo lobushushu liphantsi le-MgO-MA ikwa-2050 ℃. I-Magnesium-aluminium spinel yiminerali yendalo, exhaphake ngokuxhaphakileyo kwisanti ekufakeni, ngenxa yoko izinzile kwimichiza.

Imodyuli yokuqina ibincinci, isitena se-magnesia alumina (0.12 ～ 0.228) × 105 MPa, ngelixa isitena semagnesia si (0.6 ～ 5) × 105MPa; I-MA ingadlulisela i-MF kwi-periclase, kwaye inokutshayela i-FeO. Impendulo imi ngolu hlobo lulandelayo: FeO + MgO • AI2O3 → MgO + FeAl2O4, FeO + MgO → (Mg • Fe) O, MA ifunxa i-Fe2O3 kwaye iyanda kancinci kwaye inendawo yokunyibilika ephezulu. I-Spinel inendawo yokunyibilika ye-2135 ° C, kwaye ubushushu bayo bokuqala bokunyibilika nge-periclase buphezulu kune-1995 ° C. Ukudityaniswa kwezi zimbini kuya kuphucula ukusebenza komxokelelwane wezitena zemagnesia. Ubushushu bokunciphisa umthwalo buphezulu, kodwa ukwakheka kwe-spinel kuhamba kunye nokwandiswa kwevolumu, kwaye ukudityaniswa kunye nokukwazi ukuphinda kwenziwe kwakhona kubuthathaka, ke kufuneka ubushushu obuphezulu bokudubula. Ukuxhathisa ngokugqwesileyo kobushushu. amandla aphezulu. Ukumelana nokukhukuliseka ngamandla.