Lebenkii alumina ee Magnesia

Lebenkii alumina ee Magnesia wuxuu ka samaysan yahay magnesia sintered oo tayo sare leh iyo qiyaastii 8%budada Al2O3 saafi ah oo wanaagsan ama bauxite alumina-tayo sare leh (Al2O3> 78%, SiO2 <20%, qadar yar oo Fe2O3 iyo wasakhda kale), adoo isticmaalaya sulfite dareeraha qashinka saxarka sida xidhmooyin, alaab soo -celinaysa alkaline oo lagu sameeyay isku -darka, isku -darka, xaashida, qalajinta, dab -rididda iyo hababka kale.

Maadada magnesium oxide ee ku jirta lebenka alumina ee magnesia waa qiyaastii 85%. Waxyaabaha ku jira alumina waa 5% ilaa 10%, walxaha asaasiga ah ee jaban oo leh periclase oo ah wajiga ugu weyn ee kristal iyo magnesia-aluminium spinel oo ah wejiga kristal-ka labaad (oo ah wajiga ugu xidhnaanta). Cufnaanta muuqata ayaa guud ahaan ah 15-18%. Isuduwaha ballaarinta kuleylka waa 10.6 × 10-6/° C. Iska caabbinta naxdinta kuleylka ayaa ka fiican lebenka magnesia ee u dhigma. Sababtoo ah spinel aluminium magnesium oo leh dhibic dhalaalaysa oo sare ayaa lagu qaybiyaa shaxanka, xooggiisa heerkulka sare wuu sarreeyaa, heerkulka bilowga ee jilicsanaanta rarku wuxuu ka sarreeyaa 1580 ° C. Iska caabbinta dhoobada ayaa iyaduna ka fiican. Guud ahaan, magnesia sintered oo tayo sare leh ayaa loo adeegsadaa sida maaddada granular, iyo budo fiican oo ka kooban magnesia iyo bauxite ama clinker bauxite fudud ama alumina warshadeed ayaa lagu daray saami gaar ah, waxaana lagu helaa isku darka, sameynta iyo dabka.

1. Lebenkii alumina ee Magnesia waxaa lagu samayn karaa iyadoo lagu darayo 5-10% Al2O3 magnesia sintered. A12O3 waxaa lagu daraa budada wanaagsan oo ah qaab alumina warshadeed ama clinker bauxite sare.

2. Haddii Al2O3 lagu soo bandhigo carrada dhagaxa alumina ee sare, waxay ku qasban tahay inay soo bandhigto wasakhda sida SiO2 isla markaa, taas oo yaraynaysa dib -u -dhaca iyo xoogga heerkulka sare ee alaabta. Sidaa darteed, xaddiga alumina ee lagu daray waa inaysan noqon mid aad u badan.

3. Heerarka habraaca soo saaridda lebenyada alumina ee magnesia waxay qiyaas ahaan la mid yihiin kuwa lebenka magnesia. Kaliya waa in heerkulka dabku guud ahaan ka sarreeyo heerkulka dabka ee lebenka magnesia 30-50 ° C, oo gaaray 1750-1800 ° C.

Lebenkii alumina ee Magnesia waxay leeyihiin astaamaha soo socda:

1. Lebenkii alumina ee Magnesia waxay leeyihiin xasilooni shoog kuleyl oo wanaagsan waxayna u adkeysan karaan qaboojinta biyaha 20-25 jeer ama xitaa ka sareeya. Tani waa faa’iidadeeda ugu caansan. Lebenkii alumina ee Magnesia waxay leeyihiin xasilooni shoog fiican. Labada magnesia alumina spinel iyo periclase labaduba waxay ka tirsan yihiin nidaamka kristal cubic. Ballaarinta kuleylka ee dhinac kasta oo ka soo raaca kristalku waa isku mid, sidaa darteed ballaarinta iyo foosha ayaa labadaba ah marka heerkulku isbedbeddelo. Waa mid isku mid ah waxayna soo saartaa cadaadis kuleyl oo yar.

2. Guryaha ugu waaweyn ee lebenka alumina ee magnesia sidoo kale xoogaa way ka xoog badan yihiin kuwa lebenka magnesia. Sababtoo ah barta dhalaalaysa ee sare ee lafdhabarta magnesia-aluminium lafteeda, heerkulka jilcinta culayska ee lebenka magnesia-aluminium-ka ayaa ka fiican kan lebenka magnesia, oo gaaraya 1620 ～ 1690 ℃.

3. Halabuurka kiimikada ee lebenyada magnesia-aluminium way ku kala duwan yihiin alaab ceeriin oo kala duwan, guud ahaan MgO> 81%, Al2O3 8.7%, SiO2 <6.0%, CaO <1.5%, Fe2O3 <1.0%.

4. Dhismaha macdanta ee lebenkii alumina ee magnesia. Halabuurka macdanta, crystal ugu weyn waa periclase, iyo matrixku wuxuu ka kooban yahay magnesium ferrite, forsterite, forsterite iyo magnesia spinel.

5. Dib -u -habeynta iyo culeyska heerkulka jilicsanaanta lebenka alumina ee magnesia. Lebenkii alumina ee magnesia, kiristaaloolada periclase iyo magnesia alumina spinel ayaa sameeya qaab -dhismeed shabakad. In kasta oo qaddar yar oo ah nijaasta dhibicda dhalaalaysa ay ka buuxaan meelaha bannaan ee qaab -dhismeedka shabakadda, qaab -dhismeedka shabakaddu wali waa Awood u leeyahay inuu iska caabbiyo heerkulka sare iyo culeyska, sidaa darteed dib -u -habeynta iyo cufnaanta heerkulka jilicsanaanta ee lebenkii alumina ee magnesia ayaa aad u sarreeya, dib -u -celinta waxay gaari kartaa 2100 ℃, iyo heerkulka jilicsanaanta culeyska waa 1570 ℃.

6. Ballaarinta kuleylka iyo xasilloonida kuleylka ee lebenka magnesia-aluminium. Sababtoo ah is-weydaarsiga ballaarinta toosan ee spinel-ka magnesia-aluminium-ku waa yar yahay, is-weydaarsiga ballaarinta toosan ee leben-magnesia-aluminium aad ayuu u yar yahay. Inta u dhexeysa 20 ~ 1000 ℃, isugeynta ballaarinta toosan ee lebenka alumina ee magnesia waa 10.6 × 10-6 ℃ -1. Sababtoo ah magnesia alumina spinel ayaa kaalin ka qaadata kor u qaadista iska caabbinta shoogga kuleylka lebenka, lebenka magnesia alumina wuxuu leeyahay iska caabin shooga oo ka fiican, tirada qaboojinta biyaha ayaa ka badan 20 jeer.

7. Iska caabin caag ah oo lebenkii magnesia-aluminium ah. Sababtoo ah lebenkii magnesia-aluminiumku waxay leeyihiin cufnaan sare iyo porosity hooseysa, periclase waxaa ku wareegsan spinel magnesia-aluminium, iyo AI2O3 waa oksid dhexdhexaad dhexdhexaad ah, sidaa darteed lebenkii magnesia-aluminium Awoodda iska-caabbinta aashitada iyo nabaad-guurka alkaline waa mid aad u xoog badan.

Awoodda lebenka alumina ee magnesia si ay uga ilaaliso walxaha periclase nabaadguurka ayaa ka xoog badan kan forsterite, sidaa darteed awoodda birta magnesia alumina si ay uga hortagto wasakhda alkaline iyo dhoobada oksaydhka birta ayaa la xoojiyaa.

Lebenkii Magnesia-alumina waxay leeyihiin guryaha sare ee aan kor ku soo xusnay, sidaa darteed waxaa si weyn loogu isticmaalay alaabada dhagaxa ee saqafka foornooyinka dhalaalaya heerkulka sare sida bir-samaynta foornooyinka dab-damiska furan iyo foornooyinka dib-u-dhalaalka naxaas-dhalaaliya saamaynta fidinta nolosha foornada. Dabka weyn ee furan wuxuu gaari karaa ilaa 300 oo foorno, iyo dabka dhexe iyo kan yar ee furan wuxuu leeyahay in ka badan 1000 foorno.