Tukwane na musamman yana nufin nau'in tukwane masu siffofi na musamman na inji, na zahiri ko na sinadarai, kayan da ake amfani da su da fasahar samarwa da ake buƙata sun bambanta sosai da tukwane na yau da kullun da haɓakawa. Dangane da halaye da amfani, ana iya raba tukwane na musamman zuwa rukuni biyu: tukwane na tsari da tukwane masu aiki. Daga cikinsu, tukwane na tsari suna nufin tukwane waɗanda za a iya amfani da su azaman kayan gini na injiniya, waɗanda gabaɗaya suna da ƙarfi mai yawa, babban tauri, babban modulus na roba, juriya mai zafi, juriya mai lalacewa, juriya mai lalata, juriya ga iskar shaka, juriya ga girgizar zafi da sauran halaye.
Akwai nau'ikan yumbu na tsari da yawa, fa'idodi da rashin amfani, kuma alkiblar amfani da fa'idodi da rashin amfani sun bambanta, daga cikinsu akwai "yumbu na silicon nitride" saboda daidaiton aiki a dukkan fannoni, wanda aka sani da mafi kyawun aiki mai cikakken tsari a cikin dangin yumbu na tsari, kuma yana da fa'idodi da yawa.
Fa'idodin tukwane na silicon nitride
Ana iya raba silicon nitride (Si3N4) zuwa mahaɗan haɗin covalent, tare da [SiN4] 4-tetrahedron a matsayin sashin tsari. Ana iya ganin takamaiman matsayin atom ɗin nitrogen da silicon daga hoton da ke ƙasa, silicon yana tsakiyar tetrahedron, kuma matsayin wurare huɗu na tetrahedron suna ɗauke da atom ɗin nitrogen, sannan kowane tetrahedron uku yana raba atom ɗaya, yana faɗaɗa a sarari mai girma uku. A ƙarshe, tsarin hanyar sadarwa ya samo asali. Yawancin halayen silicon nitride suna da alaƙa da wannan tsarin tetrahedron.
Akwai tsarin kristal guda uku na silicon nitride, waɗanda sune matakai na α, β da γ, waɗanda daga cikinsu matakai na α da β sune nau'ikan silicon nitride da aka fi sani. Saboda ƙwayoyin nitrogen suna haɗuwa sosai, silicon nitride yana da ƙarfi mai kyau, tauri mai yawa da juriyar zafin jiki mai yawa, kuma taurin zai iya kaiwa HRA91~93; Kyakkyawan juriyar zafi, zai iya jure zafin jiki mai yawa na 1300~1400℃; Ƙaramin amsawar sinadarai tare da abubuwan carbon da ƙarfe yana haifar da ƙarancin haɗin gogayya; Yana mai shafawa da kansa don haka yana da juriya ga lalacewa; Juriyar tsatsa tana da ƙarfi, ban da hydrofluoric acid, baya amsawa da wasu acid marasa tsari, zafin jiki mai yawa kuma yana da juriyar iskar shaka; Hakanan yana da juriyar girgiza mai kyau, sanyaya mai kaifi a cikin iska sannan dumama mai kaifi ba zai ruguje ba; Rarrabuwar yumburan silicon nitride yana raguwa a babban zafin jiki, kuma jinkirin nakasar filastik ƙarami ne a ƙarƙashin tasirin babban zafin jiki da kaya mai tsayayye.
Bugu da ƙari, tukwanen silicon nitride suna da ƙarfi mai ƙarfi, yanayin musamman mai girma, ƙarfin lantarki mai yawa, kyawawan halayen lantarki da sauran fa'idodi, don haka yana da ƙimar aikace-aikace ta musamman a cikin yanayi mai tsanani kamar zafin jiki mai girma, babban gudu, ƙarfin watsawa mai ƙarfi, kuma ana ɗaukarsa a matsayin ɗaya daga cikin kayan yumbu masu kyau don haɓakawa da aikace-aikace, kuma sau da yawa yana zama zaɓi na farko a cikin aikace-aikace da yawa waɗanda ke buƙatar a gwada.
Lokacin Saƙo: Agusta-15-2023