Ukusetyenziswa kwe-α-alumina kwi-newiiseramikhi ze-alumina
Nangona kukho iintlobo ngeentlobo zezinto ezintsha zeseramikhi, zinokwahlulwahlulwa zibe ziindidi ezintathu ngokwemisebenzi yazo kunye nokusetyenziswa kwazo: iiseramikhi ezisebenzayo (ezaziwa ngokuba ziiseramikhi ze-elektroniki), iiseramikhi zesakhiwo (ezaziwa ngokuba ziiseramikhi zobunjineli) kunye nee-bioceramics. Ngokwezinto ezahlukeneyo ezisetyenzisiweyo, zinokwahlulwa zibe ziiseramikhi ze-oxide, iiseramikhi ze-nitride, iiseramikhi ze-boride, iiseramikhi ze-carbide kunye neeseramikhi zesinyithi. Phakathi kwazo, iiseramikhi ze-alumina zibaluleke kakhulu, kwaye izinto zazo ezikrwada yi-α-alumina powder eneempawu ezahlukeneyo.
I-α-alumina isetyenziswa kakhulu ekuveliseni izixhobo ezintsha ezahlukeneyo zeseramikhi ngenxa yamandla ayo aphezulu, ubulukhuni bayo obuphezulu, ukumelana nobushushu obuphezulu, ukumelana nokuguguleka kunye nezinye iimpawu ezintle. Ayisiyonto nje kuphela engumgubo wezinto zeseramikhi ze-alumina eziphambili ezifana nezixhobo zesekethe ezidibeneyo, amatye anqabileyo okwenziwa, izixhobo zokusika, amathambo okwenziwa, njl.njl., kodwa ingasetyenziswa njengomthwali we-phosphor, izixhobo ezichaseneyo eziphucukileyo, izixhobo zokusila ezikhethekileyo, njl.njl. Ngophuhliso lwesayensi netekhnoloji yanamhlanje, intsimi yokusetyenziswa kwe-α-alumina iyanda ngokukhawuleza, kwaye imfuno yemarike nayo iyanda, kwaye amathuba ayo abanzi kakhulu.
Ukusetyenziswa kwe-α-alumina kwiiseramikhi ezisebenzayo
Iiseramikhi ezisebenzayobhekisa kwiiseramikhi eziphambili ezisebenzisa iipropati zazo zombane, zemagnethi, ze-acoustic, ze-optical, ze-thermal kunye nezinye okanye iziphumo zazo zokudibanisa ukufezekisa umsebenzi othile. Zineepropati ezininzi zombane ezifana ne-insulation, i-dielectric, i-piezoelectric, i-thermoelectric, i-semiconductor, i-ion conductivity kunye ne-superconductivity, ngoko ke zinemisebenzi emininzi kunye nezicelo ezibanzi kakhulu. Okwangoku, ezona ziphambili ezisetyenziswe ngokoqobo kwinqanaba elikhulu ziiseramikhi zokufaka i-insulation kwii-substrates zesekethe ezidibeneyo kunye nokupakisha, iiseramikhi zokufaka i-spark plug ze-automotive, iiseramikhi ze-dielectric ze-capacitor ezisetyenziswa kakhulu kwiithelevishini nakwiirekhoda zevidiyo, iiseramikhi ze-piezoelectric ezinokusetyenziswa okuninzi kunye neeseramikhi ezinobuthathaka kwiisensors ezahlukeneyo. Ukongeza, zikwasetyenziselwa iityhubhu ezikhupha ukukhanya kwesibane se-sodium esine-high-pressure.
1. Iiseramikhi zokukhusela iiplagi zespark
Ii-spark plug insulating ceramics okwangoku zezona zisetyenziswa kakhulu kwii-ceramics kwiinjini. Ngenxa yokuba i-alumina inobushushu obuhle kakhulu bombane, amandla aphezulu oomatshini, ukumelana noxinzelelo oluphezulu kunye nokumelana nobushushu, ii-spark plugs ze-alumina insulating zisetyenziswa kakhulu kwihlabathi liphela. Iimfuno ze-α-alumina kwii-spark plugs zii-micropowders eziqhelekileyo ze-α-alumina micropowders eziphantsi kwe-sodium, apho umxholo we-sodium oxide ungo-≤0.05% kwaye ubungakanani obuphakathi be-particle yi-325 mesh.
2. Izixhobo zesekethe ezidibeneyo kunye nezixhobo zokupakisha
Iiceramics ezisetyenziswa njengezinto ze-substrate kunye nezinto zokupakisha zingcono kuneplastiki kwezi zinto zilandelayo: ukumelana nobushushu obuphezulu, ukumelana nokugqwala kweekhemikhali eziphezulu, ukuvalwa okuphezulu, ukuthintela ukungena komswakama, akukho reactivity, kwaye akukho ungcoliseko kwi-silicon ye-semiconductor ecocekileyo kakhulu. Iimpawu ze-α-alumina ezifunekayo kwi-substrates zesekethe ezidibeneyo kunye nezixhobo zokupakisha zezi: i-thermal expansion coefficient 7.0×10-6/℃, i-thermal conductivity 20-30W/K·m (ubushushu begumbi), i-dielectric constant 9-12 (IMHz), i-dielectric loss 3~10-4 (IMHz), i-volume resistivity>1012-1014Ω·cm (ubushushu begumbi).
Ngenxa yokusebenza okuphezulu kunye nokuhlanganiswa okuphezulu kweesekethe ezidibeneyo, iimfuno ezingqongqo ngakumbi zibekwa phambili kwiziseko kunye nezixhobo zokupakisha:
Njengoko ukuveliswa kobushushu kwetshiphu kusanda, kufuneka umbane ophezulu oqhuba ubushushu.
Ngesantya esiphezulu sento yokubala, kufuneka i-dielectric constant ephantsi.
I-coefficient yokwandisa ubushushu iyadingeka ukuze ibe kufutshane ne-silicon. Oku kubeka iimfuno eziphezulu kwi-α-alumina, oko kukuthi, iphuhla kwicala lokucoceka okuphezulu kunye nokuqina.
3. Isibane esikhupha ukukhanya kwe-sodium esinoxinzelelo oluphezulu
Iiseramikhi ezintleZenziwe nge-alumina ecocekileyo kakhulu, izinto eziluhlaza zineempawu zokuxhathisa amaqondo obushushu aphezulu, ukuxhathisa ukugqwala, ukugquma kakuhle, amandla aphezulu, njl.njl., kwaye zizinto ze-ceramic ezibalaseleyo. I-polycrystalline ecacileyo eyenziwe nge-alumina ecocekileyo kakhulu ene-magnesium oxide encinci, i-iridium oxide okanye izongezo ze-iridium oxide, kwaye zenziwe yi-atmospheric sintering kunye ne-hot pressing sintering, zinokumelana nokugqwala komphunga we-sodium obushushu obuphezulu kwaye zingasetyenziswa njengezibane ezikhupha ukukhanya kwe-sodium ezinoxinzelelo oluphezulu kunye nokusebenza kakuhle kokukhanyisa okuphezulu.
Ukusetyenziswa kwe-α-alumina kwiiseramikhi zesakhiwo
Njengezinto ezingaphiliyo ze-biomedical, izinto ze-bioceramic azinazo iziphumo ezinobungozi xa kuthelekiswa nezinto zesinyithi kunye nezinto ze-polymer, kwaye zihambelana kakuhle ne-bio kunye nokumelana nokugqwala kwiithishu zebhayoloji. Ziye zaxatyiswa ngakumbi ngabantu. Uphando kunye nokusetyenziswa kweklinikhi kwezinto ze-bioceramic kuye kwaphuhliswa ukusuka ekutshintshweni kwexesha elifutshane kunye nokuzaliswa ukuya ekufakweni okusisigxina nokuqinileyo, kunye nokusuka kwizinto zebhayoloji ezingasebenziyo ukuya kwizinto ezisebenzayo kwibhayoloji kunye nezinto ezidityanisiweyo zesigaba esineenxalenye ezininzi.
Kwiminyaka yakutshanje, i-poreiiseramikhi ze-aluminazisetyenziselwe ukwenza amalungu amathambo okwenziwa, amalungu edolo okwenziwa, iintloko zefemoral zokwenziwa, amanye amathambo okwenziwa, iingcambu zamazinyo okwenziwa, izikrufu zokuqinisa amathambo, kunye nokulungiswa kwe-cornea ngenxa yokumelana kwazo nokugqwala ngamakhemikhali, ukumelana nokuguguleka, uzinzo oluhle kubushushu obuphezulu, kunye neempawu ze-thermoelectric. Indlela yokulawula ubungakanani bembobo ngexesha lokulungiselela iiseramikhi ze-alumina ezinemibhobho kukuxuba amasuntswana e-alumina obungakanani obahlukeneyo bezinto ezincinci, ukufunxa i-foam, kunye nokutshiza amasuntswana. Iipleyiti ze-aluminium zinokuphinda zifakwe i-anodized ukuvelisa ii-pores ze-nano-scale microporous channel-type pores.