Qaar ka mid ah qashinka warshadaha ayaa lagu muujiyay inay faa'iido u leeyihiin soo saarista dhoobada dhoobada ah. Qashinka warshaduhu waxay qani ku yihiin qaar ka mid ah oksaydhyada birta sida silica (SiO2) iyo alumina (Al2O3). Tani waxay siinaysaa qashinka suurtagalka ah in loo isticmaalo ilo bilow ah oo loogu talagalay diyaarinta dhoobada mullite. Ujeedada warqaddan dib-u-eegista waa in la ururiyo oo dib loo eego hababka diyaarinta dhoobada badan ee kala duwan ee loo adeegsaday noocyo kala duwan oo qashinka warshadaha ah sidii qalab bilow ah. Dib-u-eegiddu waxay sidoo kale sharraxaysaa heerkul-ku-soo-noqoshada iyo waxyaabaha kiimikada lagu daro ee loo isticmaalo diyaarinta iyo saameynteeda. Isbarbardhigga labadaba xoogga farsamada iyo ballaadhinta kulaylka ee dhoobada dhoobada ah ee la soo sheegay ee laga diyaariyey qashinka warshadaha ee kala duwan ayaa sidoo kale looga hadlay shaqadan.
Mullite, oo inta badan lagu tilmaamo 3Al2O3∙2SiO2, waa walxo dhoobo ah oo aad u fiican taas oo ay ugu wacan tahay sifooyinkeeda jireed ee aan caadiga ahayn. Waxay leedahay meel dhalaalaysa oo sare, iskudar hoose oo balaadhinta kulaylka, xoog sare oo heerkul sare ah, waxayna leedahay shoog kulaylka iyo caabbinta gurguurta labadaba [1]. Qalabkan kulaylka iyo farsamada ee aan caadiga ahayn waxay awood u siinayaan walxaha in loo isticmaalo codsiyada sida refractories, furniture kiln, substrates for catalytic adaptors, tubooyinka foornada, iyo gaashaammada kulaylka.
Mullite waxaa laga heli karaa oo kaliya sida macdanta yar ee Mull Island, Scotland [2]. Sababtoo ah jiritaankeeda naadirka ah ee dabiiciga ah, dhammaan ceramics-ka mullite ee loo isticmaalo warshadaha waa dad-sameeyay. Cilmi baaris badan ayaa la sameeyay si loogu diyaariyo ceramics-mullite iyadoo la adeegsanayo horudhacyo kala duwan, laga bilaabo mid ka mid ah kiimikooyinka heerka warshadaha / shaybaarka [3] ama macdanta aluminosilicate ee dabiiciga ah [4]. Si kastaba ha ahaatee, qiimaha alaabtan bilawga ah waa qaali, kuwaas oo la farsameeyey ama la soo saaray ka hor. Muddo sanado ah, cilmi-baarayaashu waxay raadinayeen beddelaad dhaqaale si ay u farsameeyaan dhoobada mullite. Sidaa darteed, horudhacyo badan oo mullite ah oo ka soo jeeda qashinka warshadaha ayaa lagu soo warramey suugaanta.Qashinkan warshaduhu waxay leeyihiin waxyaabo badan oo silica iyo aluminium waxtar leh, kuwaas oo ah kiimikooyinka muhiimka ah ee loo baahan yahay si loo soo saaro dhoobada mullite. Faa'iidooyinka kale ee isticmaalka qashinka warshadaha waa tamarta iyo badbaadinta kharashka haddii qashinka la leexiyo oo dib looga faa'iidaysto sidii qalab injineernimo. Intaa waxaa dheer, tani waxay sidoo kale gacan ka geysan kartaa dhimista culeyska deegaanka iyo kor u qaadida faa'iidada dhaqaale.
Si loo baaro in qashinka saafiga ah ee electroceramics loo isticmaali karo in lagu farsameeyo dhoobada mullite, wasakhda electroceramics saafi ah lagu qasay budada alumina iyo wasakhda electroceramics saafi ah sida alaabta ceeriin ayaa la barbardhigay. sifooyinka dhoobada mullite ayaa la baaray. XRD iyo SEM ayaa loo isticmaalay in lagu barto halabuurka wajiga iyo qaab-dhismeedka yar yar.
Natiijooyinku waxay muujinayaan in maaddada mullite ay kor u kacday heerkulka sintering, iyo isla mar ahaantaana cufnaanta bulk ayaa kordhay. Maaddooyinka cayriin ayaa ah qashinka saafiga ah ee elektroceramics, sidaas awgeed dhaqdhaqaaqa qulqulaya waa ka weyn yahay, habka qulqulaya waa la dardargelin karaa, cufnaanta sidoo kale waa la kordhiyaa. Marka mullite-ka lagu diyaariyo qashinka elektroceramics-ka, cufnaanta bulk iyo xoogga cufnaanta ayaa ugu weyn, porosity-gu waa yar yahay, sifooyinka jireed ee dhamaystiran ayaa noqon doona kuwa ugu fiican.
Iyada oo ay sabab u tahay baahida loo qabo beddelka qiimaha jaban iyo bey'adda u wanaagsan, dadaallo badan oo cilmi-baaris ah ayaa isticmaalay noocyo kala duwan oo qashinka warshadaha ah sidii qalab bilow ah si ay u soo saaraan dhoobada mullite. Hababka habaynta, heerkulbeegyada qallafsan, iyo waxyaabaha kiimikada lagu daro ayaa dib loo eegay. Habka hab-socodka hab-dhaqameedka ee ku lug leh isku-darka, riixida, iyo falcelinta falcelinta horudhaca mullita ayaa ahaa habka ugu badan ee la isticmaalo sababtoo ah fududaantiisa iyo waxtarkiisa qiimaha. Inkasta oo habkani uu awood u leeyahay in uu soo saaro dhoobada dhoobada ah, daldaloolada muuqda ee dhoobada mullite ayaa la sheegay inay ka hooseyso 50%. Dhanka kale, shubista barafka ayaa la tusay inay awood u leedahay inay soo saarto dhoobada dhoobada ah ee aadka u daloosha, oo leh dalool cad oo 67% ah, xitaa heerkul aad u sarreeya oo ah 1500 °C. Dib u eegis lagu sameeyay heerkulka sintering iyo kiimikooyinka kala duwan ee lagu daro ee loo isticmaalo soo saarista mullite ayaa la sameeyay. Waa suurad wacan in loo isticmaalo heerkul ka sarreeya 1500 °C wax-soo-saarka mullite, sababtoo ah heerka falcelinta sare ee u dhexeeya Al2O3 iyo SiO2 ee hordhaca ah. Si kastaba ha ahaatee, maadada silica ee xad-dhaafka ah ee la xiriirta wasakhda hore waxay u horseedi kartaa muunada doorsoomidda ama dhalaalidda inta lagu jiro heerkul sare. Marka laga hadlayo waxyaabaha kiimikada lagu daro, CaF2, H3BO3, Na2SO4, TiO2, AlF3, iyo MoO3 ayaa lagu soo warramey inay yihiin gargaar wax ku ool ah si loo yareeyo heerkulka sinjiga halka V2O5, Y2O3-doped ZrO2 iyo 3Y-PSZ loo isticmaali karo si kor loogu qaado cufnaanta dhoobada mullite. Ku-doojinta walxaha kiimikaad sida AlF3, Na2SO4, NaH2PO4 · 2H2O, V2O5, iyo MgO waxay caawisay koritaanka anisotropic ee shabaqyada mullite, kaas oo markii dambe kor u qaaday xoogga jireed iyo adkaanta dhoobada dhoobada ah.
Waqtiga boostada: Agoosto-29-2023