Menene bambanci tsakanin alumina, corundum da sapphire?

Akwai da yawa incarnations na alumina. Lokacin da abokai da yawa suka ji sunaye irin su “alumina”, “corundum”, “ruby” da “sapphire”, ba za su iya bambanta bambanci tsakanin waɗannan ba kuma sukan ji rudani. Tabbas, wannan yanayin kuma yana da alaƙa da rashin daidaituwa na yau da kullun don nau’ikan alumina da yawa. Domin bambance su, marubucin zai haɗa muku wasu bayanai don taimaka muku gano waɗannan sharuɗɗan.

1. Alumina

Alumina, wanda aka fi sani da bauxite, yana da nauyin 3.9-4.0g/cm3, wurin narkewa na 2050 ° C, wurin tafasa 2980 ° C, kuma ba ya narkewa a cikin ruwa. Ana iya fitar da alumina daga bauxite a cikin masana’antu. . Daga cikin waɗannan bambance-bambancen Al2O3, α-Al2O3 kawai ya tsaya tsayin daka, kuma sauran siffofin crystal ba su da tabbas. Yayin da zafin jiki ya tashi, waɗannan sifofin kristal na wucin gadi za su canza zuwa α-Al2O3.

A cikin lattice crystal na α-alumina, oxygen ions suna kusa da cushe a cikin hexagons, kuma Al3 + an rarraba su cikin daidaituwa a tsakiyar ligand octahedral kewaye da oxygen ions. Ƙarfin lattice yana da girma sosai, don haka wurin narkewa da wurin tafasa suna da girma sosai. Alpha-alumina ba ya narkewa a cikin ruwa da acid. Hakanan an san shi da aluminum oxide a cikin masana’antu kuma shine ainihin albarkatun ƙasa don shirye-shiryen aluminum na ƙarfe. Bugu da ƙari, ana iya amfani da shi don shirya abubuwa daban-daban na refractory, kayan abrasive, da substrates don haɗaɗɗun da’irori. Bugu da ƙari, α-alumina mai tsafta kuma ɗanyen abu ne don samar da corundum na wucin gadi, rubies na wucin gadi da sapphires.

γ-type alumina ana samar da shi ta hanyar bushewar aluminum hydroxide a zafin jiki na 500-600 ° C, kuma ana kiransa alumina mai kunnawa a cikin masana’antu. A cikin tsarinsa, ions oxygen suna kusan cika da yawa a cikin jiragen sama na tsaye, kuma Al3+ ana rarraba ba bisa ka’ida ba a cikin octahedral da tetrahedral vooids kewaye da ions oxygen. Ana iya amfani da shi azaman masu haɓakawa, masu ɗaukar hoto, masu tallatawa, desiccants, da sauransu a cikin masana’antu. Masu sha’awar wannan samfurin za su iya bincika post na “Shiri da Aikace-aikacen Alumina Mai kunnawa”.

A takaice: Ana iya ɗaukar Alumina a matsayin wani abu wanda ya ƙunshi Al2O3 (ya ƙunshi wasu ƙazanta, yawanci ba tsarki ba). Irin wannan nau’in abu yana da nau’i-nau’i daban-daban na crystal, nau’i daban-daban na samfurori, da nau’i daban-daban, waɗanda ke wakiltar samfurori daban-daban. , Ana amfani da su a fannoni daban-daban.

High alumina ball-babban bangaren shine alumina

2. Corundum da wucin gadi corundum

Lu’ulu’u na alumina irin α da ke faruwa a zahiri ana kiran su corundum, kuma galibi suna nuna launuka daban-daban saboda datti daban-daban. Corundum gabaɗaya shuɗi ne ko launin toka mai rawaya, tare da gilashi ko lu’u lu’u lu’u-lu’u, yawa 3.9-4.1g/cm3, taurin 8.8, na biyu kawai zuwa lu’u-lu’u da siliki carbide, kuma yana iya jure yanayin zafi.

Halitta yellow corundum

Akwai galibi nau’ikan corundum na halitta guda uku a yanayi: a. Corundum mai inganci, wanda aka fi sani da gemstone: sapphire ya ƙunshi titanium, ruby ​​​​ya ƙunshi chromium, da sauransu; b talakawa corundum: baki ko launin ruwan kasa ja; c emery: za a iya raba shi zuwa Emerald emery da limonite emery , Yana da nau’i na nau’i na crystal tare da ƙananan taurin. Daga cikin nau’ikan corundum guda uku da ke sama, na farko ana amfani da shi ne don kayan ado, na biyun kuma ana iya amfani da su azaman abrasives don yin ƙafafun niƙa, dutsen mai, sandpaper, zane ko foda, goge baki, da sauransu.

Saboda abubuwan da ake samarwa na corundum na halitta ba su da yawa, corundum da ake amfani da shi a masana’antu galibi corundum ne na wucin gadi maimakon samfuran corundum na halitta.

Alumina masana’antu shine foda mai lu’ulu’u mai laushi tare da tsari mai laushi da sako-sako, wanda bai dace da hulɗar lu’ulu’u na Al2O3 tare da juna ba kuma don haka bai dace da sintering ba. Yawancin lokaci bayan calcination ko fusion recrystallization, γ-Al2O3 ya zama α-Al2O3 (corundum) don sintering da densification. Dangane da hanyar samarwa, an raba corundum zuwa haske kone (1350 ~ 1550 ℃) corundum (wanda kuma aka sani da hasken kona α-Al2O3), sintered (1750 ~ 1950℃) corundum, da kuma fused corundum.

Corundum na wucin gadi-farin corundum yashi

A takaice: al’ada ce a kira α-crystal alumina azaman corundum. Ko corundum na halitta ne ko corundum na wucin gadi, babban abin da ke cikin corundum shine alumina, kuma babban lokacin crystal shine α-alumina.

3. Gem grade corundum da ruby ​​na wucin gadi, sapphire

Corundum mai inganci wanda aka haɗe tare da ƙananan ƙazantattun oxide daban-daban shine sanannen ruby ​​da sapphire, wanda shine kayan yin kayan ado masu daraja, kuma za’a iya amfani da barbashi don yin jigilar kayan aiki da agogo.

shuɗin yaƙutu

A halin yanzu, kira na ja sapphire ya hada da hanyar narkewar harshen wuta (hanyar narkewar wuta), hanyar ruwa, hanyar hydrothermal da sauransu. Daga cikin su, yanayin fasaha na hanyar hydrothermal yana da girma kuma mai tsanani, kuma wahalar ya fi girma, amma

A halin yanzu, kira na ja sapphire ya hada da hanyar narkewar harshen wuta (hanyar narkewar wuta), hanyar ruwa, hanyar hydrothermal da sauransu. Daga cikin su, hanyar hydrothermal yana da babban yanayin fasaha da kuma yanayin fasaha mai tsanani. Duk da haka, haɓakar lu’ulu’u masu daraja ya fi kama da lu’ulu’u masu daraja na halitta. Zai iya zama mafi yawan karya, kuma gaskiya da karya ba za a iya bambanta ba. Lu’ulu’u masu daraja da aka girma ta wannan hanya sun hada da emeralds, lu’ulu’u, yadudduka, da dai sauransu.

Jajayen wucin gadi da sapphire ba kawai iri ɗaya ne da samfuran halitta a cikin bayyanar ba, har ma a cikin zahiri da sinadarai da kaddarorin gani, amma farashin shine kawai 1/3 zuwa 1/20 na samfuran halitta. Ƙarƙashin na’urar hangen nesa kawai za a iya samun ƙananan iska a cikin duwatsu masu daraja ta wucin gadi Kumfa suna zagaye, kuma kumfa na iska a cikin kayan halitta suna da lebur.

A takaice: ko da yake alumina, corundum, ruby ​​da sapphire suna da sunaye daban-daban, amma siffarsu, taurinsu, kaddarorinsu, da amfaninsu ma sun bambanta, amma babban sinadaren su shine alumina. Babban nau’in crystal na corundum shine nau’in alumina α. Corundum wani abu ne na polycrystalline α-alumina, kuma corundum mai inganci (corundum-grade corundum) samfuri ne na alumina guda ɗaya.

Saboda gazawar ilimin marubucin, labarin ya yi karin haske kan maganganun da ba su dace ba. Ina kuma rokon kwararrun masana’antu don neman shawara, na gode.