Yadda ake yin foda na Silicon Carbide

Silicon carbide, wanda aka fi sani da carborundum, yana da tauri kamar lu'u-lu'u kuma yana da matuƙar juriya ga gogewa. Bugu da ƙari, halayen seramiki na sa sun sa ya dace da yanayi mai zafin gaske da kuma yanayi mai ƙarfin lantarki.

Sakamakon samarwar tsarin Lely yana fitowa a cikin foda wanda za a iya yanke shi ya zama lu'u-lu'u na moissanite don amfani a matsayin lu'u-lu'u, yayin da masana'antun kuma ke amfani da shi wajen kera kayan gogewa da samfuran da ke buƙatar ƙarfi.

Tushe

Silicon carbide (SiC), wanda kuma ake kira carborundum /krbnm/, haɗin sinadarai ne mai matuƙar tauri na silicon da carbon wanda ke samuwa a halitta a matsayin ma'adinin moissanite kuma ake kera shi da yawa a matsayin abin gogewa tun ƙarshen ƙarni na 19. Haɗa SiC don samar da keramiki mai tauri ko ƙara masa nitrogen, phosphorus, beryllium ko aluminum na iya samar da semikonduktor na n-ko p-type.

Yawanci ana samar da SiC na masana'antu ta hanyar tsarin Acheson, inda ake dumama yashi mai silika tare da tushen carbon kamar koken man fetur zuwa zafin gaske a cikin murhu mai buɗewa, wanda ke samar da ƙwayoyi masu launin kore ko baƙi dangane da matakin tsarkinsu.

An san SiC da ingantacciyar gudanar da zafi da juriya ga tsatsa. Tare da ƙarancin ƙimar faɗaɗawar zafi, babban rabo tsakanin ƙarfi da tauri, daidaiton sinadarai da sauƙin sarrafawa ta injina, yana zama muhimmin albarkatun ƙasa a aikace-aikacen masana'antu da dama kamar kayan hana ƙonewa masu inganci, kayan gogewa da keramiki [16].

Sarrafawa

Silicon Carbide (SiC) kayan seramiki ne na fasaha mai kaddarori na musamman ciki har da rashin yin tasiri na sinadarai a kowane zazzabi, juriya ga bugun zafi, da kuma sauƙin haɗawa (sinterability). Ana amfani da SiC a fannoni daban-daban na seramiki na fasaha, ciki har da ƙera kayan cikin murhu da na'urorin sarrafa ruwa, da kuma bearings da sassan da ke saurin lalacewa. Ƙarin amfani da SiC sun haɗa da matattarar ƙurar diesel da kariyar ballistics. Washington Mills tana ba da injinan murƙusawa, niƙa da rarrabewa waɗanda za su iya samar da kayan albarkatu masu cika ƙa'idodin ANSI, FEPA da JIS.

Furfur SiC na iya bambanta a girman ƙwayoyinsu dangane da yanayin farkonsu da tushen carbon. Wani shahararren tsarin shirya samar da SiC shi ne ta hanyar rage carbon da zafi; wannan yana haɗa amsawar haɗin gwiwa na ɗaya mole na SiO2 (ƙasa da mech 200) tare da mol 1.5–3 na tushen carbon; amfani da leaching na acid, dumama da amsawar ruwan da aka samu zai hana samar da carbon na gilashi.

Foda-foda na SiC da aka samar ta hanyar nazarin XRD na yawan adadi ana ƙara nazarinsu ta amfani da siffar ƙwayoyi, tsarin girman ƙwayoyi da nazarin fadin saman musamman. Muhimman halaye sun haɗa da siffar ƙwayoyi, tsarin girman ƙwayoyi da fadin saman musamman. Yawanci ƙwayoyin SiC suna nuna tsarin lebur mai yankewa-yankewa tare da ƙananan tsarin da ke da lahani, waɗanda ake ganin su a matsayin raga-ragan dislocation a kan iyakokinsu – wani hali marar so wanda zai iya yin illa ga tsarin sintering.

Halaye

Silicon carbide na da halaye na musamman da dama da ke ba shi damar amfani a fannoni daban-daban na masana'antu. Musamman, yana da matuƙar tauri, tare da ƙimar tauri na Mohs 9. Bugu da ƙari, wannan kayan ba ya yin tasiri da sinadarai, yana da ƙarfin juriya ga gogayya, yana iya jure zafi har zuwa manyan zazzabi, kuma yana da ƙarfi na jan ƙarfe da ƙananan ƙimar faɗaɗawar zafi – waɗannan dukkanin halayen sun sa silicon carbide ya dace don amfani a masana'antu da dama.

Hanyoyin samar da silicon carbide suna da matuƙar tasiri kan halayensa da amfaninsa. Edward Goodrich Acheson ya ƙirƙiri hanyar Acheson, wadda ke haɗa dumama haɗin yashi quartz, koke na man fetur da ƙananan yankakken itace zuwa matakan zafi masu matuƙar girma domin haifar da martanin sinadarai da ke samar da kristalan silicon carbide – waɗannan kristalan za a iya nika su zuwa foda ko a zuba su cikin ingots don siyarwa.

Ana yawan amfani da wannan foda mai gogewa a masana'antar sararin samaniya da ta motoci wajen gogewa da shafe sassa domin samun daidaitattun girma da kammala mai laushi, yayin da ake amfani da shi a keramiki, kera gilashi da kuma samar da ƙarfe da sauran ƙarafa. Kamfanin Alter Technology ya ƙirƙiri wani kewayen rediyo da wannan kayan wanda zai iya jure mummunan yanayin sararin samaniya.

Neman aikace-aikace

Seramiki na silicon carbide kayan nonoxide ne mai fice da aikace-aikace da dama saboda tsaukinsa (tsaukinsa na Mohs > 9), rashin amsawa da sinadarai, ƙarancin ƙimar faɗaɗa zafi da juriya ga zafi da bugun ƙarfi. Ana amfani da silicon carbide a matsayin sassa masu juriya ga gogewa a cikin kayan gogewa ko a matsayin sassa masu juriya ga gogewa a cikin seramiki masu juriya ga zafi, da kuma a aikace-aikacen semikonduktor da na lantarki saboda kaddarorin gudanar da zafi.

Don samar da SiC, masana'antun suna fara haɗa silica mara tsari da carbon a zafin jiki mai yawa – galibi coke na kwal a matsayin tushen carbon – kafin su niƙa shi sosai su kuma gauraya shi da ƙananan adadin bauxite don samar da preform. Bayan haka, ana yin doping ta hanyar nitrogen (n-type SiC) ko ta hanyar boron, aluminium, da gallium (p-type SiC), gwargwadon aikace-aikacen da ake so.

Masu kera suna amfani da wannan preform don samar da silicon carbide mai siffar cubic ta hanyar haɗawa ta hanyar amsa sinadarai ko kuma hanyar ajiyar tururin sinadarai. Haɗawa ta hanyar amsa sinadarai ita ce hanyar da aka fi amfani da ita; wannan na haɗawa da dumama shi zuwa digiri Celsius 1410 da ƙara masa nitrogen ko boron don samar da SiC na nau'in n. Ajiyar tururin sinadarai na buƙatar kuzari da kayan aiki masu yawa sosai a cikin tsarin sa; haɗawa ta hanyar amsa sinadarai na buƙatar kaɗan sosai.

Foda na SiC mai darajar semikonduktor mai gudanar da wutar lantarki an ƙera shi ne don biyan buƙatun haɓaka na musamman na hanyoyi daban-daban na haɓaka kristal ɗaya na silicon carbide mai gudanar da wutar lantarki na nau'in n na ƙarni na uku. Wannan nau'in foda yana da rarraba girman ƙwayoyi mafi dacewa tare da ƙarancin ramuka, yana ba da matakan tsarkin samfur fiye da 6N.