IiCeramics zeBoron Carbide: Ukwazisa ngoPhando lwezeNzululwazi, Iipropati, kunye neZicelo zenguquko ze-Ultra-Hard Advanced Material
1. Intshayelelo yeBoron Carbide: Umbandela Ogqwesileyo
I-Boron carbide (B ₄ C) ime njengenye yeemveliso ezenziweyo ezimangalisayo ezivunyiweyo kwiimveliso zangoku zophando lwezenzululwazi, yahlulwe ngokubekwa kwayo phakathi kwezona mathiriyeli zinzima eMhlabeni, igqithe nje ngedayimane kunye ne-cubic boron nitride.
(Boron Carbide Ceramic)
Yaqala ukwenziwa ngenkulungwane ye-19, I-boron carbide iye yavela ngokwenene kwi-labhoratri yokufuna ukwazi ukuya kwindawo ebalulekileyo kwiinkqubo zoyilo olusebenza kakhulu., ukhuseleko ezintsha, kunye nezixhobo zenyukliya.
Indibaniselwano yayo ekhethekileyo yokuqina okugqithisileyo, ukuxinana okuncitshisiweyo, i-neutron ephezulu yokufunxa cross-icandelo, kunye nozinzo olukhethekileyo lweekhemikhali luyenza ibaluleke kakhulu kwiindawo apho imathiriyeli eqhelekileyo isilela khona.
Eli nqaku linika uphononongo olubanzi kodwa olufikelelekayo lwe-boron carbide ceramics, ukuntywila kwisakhiwo sayo seathom, iindlela zokudibanisa, Iipropathi ezinoomatshini nezomzimba zokuhlala okanye zorhwebo, kunye neentlobo ngeentlobo zezicelo eziphambili eziphakamisa iimpawu zayo ezingaqhelekanga.
Injongo kukuvala isithuba phakathi kokuqonda kweklinikhi kunye nokusetyenziswa okusebenzayo, ukunika abafundi ubunzulu, Ukuqonda okucwangcisiweyo kanye kanye ngendlela le nto imangalisayo yeceramic ibumba itekhnoloji yangoku.
2. Ubume beAtomic kunye neKhemistri eSisiseko
2.1 I-Crystal Latticework kunye neempawu zoBonding
I-Boron carbide ikhazimla kwisakhelo serhombohedral (iqela lengingqi i-R3m) kunye neseli yesixhobo esinzima esithatha i-stoichiometry eguquguqukayo, ngokwesiqhelo ukusukela ku B ₄ C ukuya ku B ₁₀. IZIHLANU C.
Isiseko esisisiseko sesi sakhiwo yi-12-atom icosahedra equlunqwe ubukhulu becala ziiathom zeboron., zidityaniswe ngamatyathanga amathathu-athom athe tye anweba i-crystal latticework.
I-icosahedra ngamaqela azinzile kakhulu ngenxa yobudlelwane obuqinileyo phakathi kwenethiwekhi ye-boron., ngelixa amatyathanga e-inter-icosahedral– ngokwesiqhelo iqulathe C-B-C okanye B-B-B amalungiselelo– idlala indima ebalulekileyo ekusekeni izixhobo zoomatshini kunye nezakhiwo zokuhlala zedijithali.
Esi sitayela sikhethekileyo sikhokelela kwimveliso enezinga eliphezulu lokubambisana ngokubambisana (ngaphaya 90%), ejongene ngqo nokuqina kwayo okumangalisayo kunye nokuzinza kwe-thermal.
Ukubonakala kwekhabhoni kwiindawo zekhonkco kwandisa ukuzinza kwezakhiwo, ukanti ukungangqinelani kwe-stoichiometry efanelekileyo kunokwazisa iziphene eziphembelela ukusebenza kakuhle koomatshini kunye nokuqina.
(Boron Carbide Ceramic)
2.2 I-Compositional Irregularity kunye ne-Flaw Chemistry
Ngokungafaniyo neekeramics ezininzi kunye nokhathalelo lwe-stoichiometry, I-boron carbide ibonisa uluhlu olubanzi lwe-homogeneity, ukuvumela ukuhluka okukhulu kwi-boron-to-carbon ratio ngaphandle kokuphazamisa isakhelo sekristale epheleleyo.
Oku kuziqhelanisa kwenza kube lula kwiipropati ezilungiselelwe usetyenziso oluthile, nangona ikwanika imingeni ekuqhubeni nasekufaniseni ngokufanelekileyo.
Iziphene ezifana nokunqongophala kwekhabhoni, ukuvuleka kwebhoron, kunye nokugqwethwa kwe-icosahedral kuxhaphakile kwaye kunokuchaphazela ubulukhuni, ukuqina kokuqhekeka, kunye ne-conductivity yombane.
Njengokuba, phantsi kwe-stoichiometric make-ups (ibhoron-etyebileyo) ikholisa ukubonisa ubulukhuni obuninzi kodwa iyancipha ukomelela kokwaphuka, ngelixa iinguqu ezityebileyo zekhabhoni zingabonisa ukuphuculwa kwe-sinterability kwinkcitho yobunzima.
Ukuqonda kunye nokulawula ezi ziphene kugxininiso olubalulekileyo kuphando oluphambili lwe-boron carbide, ngokukodwa ukunyusa ukusebenza kakuhle kwikhaka kunye nezixhobo zenyukliya.
3. IiNdlela zokuHlanganisa kunye nobuChwephesha bokuLungisa
3.1 Iindlela eziphambili zokuVelisa
I-Boron carbide powder yenziwa ikakhulu ngokuncitshiswa kwe-carbothermal yobushushu obuphezulu, inkqubo apho boric acid (H ₃ EZIMBINI EZINTATHU) okanye i-boron oxide (B ZIMBINI O ₃) iphendulwa ngezixhobo zekhabhoni ezifana ne-oyile coke okanye i-charcoal kwisithando sombane se-arc.
Ukusabela kuyaqhubeka njengoko kuhambelana:
B ZIMBINI O ₃ + 7C → 2B EZINE C + 6CO (igesi)
Le nkqubo yenzeka kumanqanaba obushushu ukuya ngaphaya 2000 °C, ukubiza igalelo elibalulekileyo lamandla.
Isiphumo sobukrwada B FOUR C kusemva kokuba kugaywe kwaye kucocwe ukususa ikharbhon ephindaphindayo kunye neeoksidi ezingachatshazelwanga..
Iindlela ezizezinye zibandakanya ukunciphisa i-magnesiothermic, i-laser-assisted synthesis, kunye ne-plasma arc synthesis, ezibonelela ngolawulo olungcono kubungakanani beqhekeza kunye nobunyulu nangona kunjalo zithintelwe kwimveliso encinci okanye ethile..
3.2 Ubunzima boxinaniso kunye nokuSintering
Phakathi kowona mceli mngeni ubalulekileyo kwimveliso ye-boron carbide ceramic kukufumana uxinaniso olupheleleyo ngenxa yokubambana okuqinileyo kunye nokunciphisa umlinganiso wokuzabalaza..
Isiqhelo esingenaxinzelelo sintering sikholisa ukukhokelela kumanqanaba e-porosity ngaphezulu 10%, ibeka emngciphekweni ukuqina komatshini kunye nokusebenza kakuhle kwebhola.
Ukuloyisa oku, iindlela zoxinaniso eziqhubela phambili zisetyenziswa:
Ukutyhala okushushu (HP): Ibandakanya ukusetyenziswa ngaxeshanye kobushushu (ngokuqhelekileyo 2000– 2200 °C )kunye noxinzelelo lwe-uniaxial (20– 50 MPa) kwindawo engenzi nto, ukuvelisa kufutshane-thiyori ubukhulu.
Ukucinezela kwe-Isostatic ngokufudumeleyo (I-HIP): Isebenzisa ubushushu obuphezulu kunye noxinzelelo lwegesi ye-isotropic (100– 200 MPa), ukususa ama-pores angaphakathi kunye nokunyusa ukuzinza komatshini.
Intlantsi yePlasma Sintering (SPS): Isebenzisa ipulsed ekhoyo ngokuthe ngqo ukutshisa ngokukhawuleza umgubo ohlangeneyo, ukwenza uxinaniso kumanqanaba obushushu asezantsi kunye namaxesha amafutshane kakhulu, ukugcina ulwakhiwo oluhle lweenkozo.
Izongezo ezifana nekhabhoni, isilicon, okanye shift metal borides zidla thaca ukukhuthaza ukusasazwa komda weenkozo kunye nokunyusa sinterability, nangona kufuneka zilawulwe ngononophelo olukhulu ukuze zihlale zicacile kukuqina okuthobayo.
4. Indawo yokuHlala ngoomatshini kunye neyoMzimba
4.1 Ukuqina okuKhethekileyo kunye noKuxhathisa ukuNxitywa
IBoron carbide idume ngobulukhuni bayo beVickers, ngokuqhelekileyo ihluka ukusuka 30 ukuya 35 Inqaku eliphakathi, ukuyibeka phakathi kwezona mathiriyeli zinzima ezaziwayo.
Oku kuqina kumandla kuguqula ukuxhathisa okuchukumisayo ekunxibeni okurhawukileyo, ukwenza i-B EZINE C igqwese kwizicelo ezifana nemilomo yokuqhunyiswa kwesanti, izixhobo zokunciphisa, kwaye banxibe iipleyiti emigodini kunye nezixhobo ezikruqulayo.
Isixhobo sokunxiba kwi-boron carbide sibandakanya i-microfracture kunye ne-grain pull-out ngokuchasene ne-deformation yeplastiki, uphawu lweeporcelains ezibuthathaka.
Nangona kunjalo, ukuqina kwayo okuphantsi (ngokuqhelekileyo 2.5– 3.5 MPa · m 1ST / MBINI) yenza kube lula ukwaphula usasazo phantsi kweempembelelo zokulayisha, ifuna uyilo olunenkathalo kwizicelo ezidlamkileyo.
4.2 Uxinano oluphantsi kunye namandla eeNkcukacha eziPhakamileyo
Ngokuxinana ngokurhabaxa 2.52 g/cm EZINTATHU, I-boron carbide iphakathi kwezona ndawo zikhaphukhaphu zokwakhiwa kweporcelain ezikhoyo, usebenzisa inzuzo enkulu kwizicelo ezinobunzima bobunzima.
Oku kuxinana okuphantsi, idityaniswe nokuqina koxinzelelo oluphezulu (ngaphaya 4 GPA), ikhokelela kwiinkcukacha ezimangalisayo amandla (ubungakanani bokuqina ukuya koxinaniso), Kubalulekile kwi-aerospace kunye neenkqubo zokukhusela apho ukunciphisa ubunzima kubalulekile.
Umzekelo, kwisikrweqe somntu kunye nesithuthi, B EZINE C inika ukhuseleko lweprimiyamu ubunzima obuthelekiswa nentsimbi okanye i-alumina, ukuvumela ukukhanya, ngakumbi iinkqubo zokhuseleko mobile.
4.3 Thermal kunye Uzinzo Chemical
I-Boron carbide ibonisa ukuzinza okuphezulu kwe-thermal, ukugcina amakhaya ayo oomatshini kangangoko 1000 ° C kwindawo engasebenziyo.
Inendawo yokunyibilika ephezulu ngeenxa zonke 2450 ° C kunye nokuncipha komlinganiso wokukhula kobushushu (~ 5.6 × 10 ⁻⁶/ K), ukongeza ukuxhathisa ukothuka okukhulu kwe-thermal.
Ngekhemikhali, ayikhuselekanga kakhulu kwiiasidi (ngaphandle kweeasidi ze-oxidizing njenge-HNO ₃) kunye neentsimbi ezinyibilikisiweyo, ukuyenza ilungele ukusetyenziswa kwiatmospheri zemichiza eqatha kunye nezityalo zamandla eathom.
Nangona kunjalo, I-oxidation iba yinto eninzi kakhulu 500 ° C emoyeni, ukwenza i-boric oxide kunye ne-carbon dioxide, enokophula ukunyaniseka kwendawo engaphezulu ngokuhamba kwexesha.
Iingqimba ezikhuselayo okanye ulawulo lokusingqongileyo zihlala zifuneka kwiingxaki ze-oxidizing zobushushu obuphezulu.
5. Izicelo eziMfihlo kunye nesiphumo soBugcisa
5.1 Ukhuseleko lweBallistic kunye neziSombululo zeShield
I-Boron carbide yimathiriyeli yembombo kwikhaka langoku elikhaphukhaphu ngenxa yomxube wayo ongalinganiyo wokuqina kunye nokuncipha kobunzima..
Isetyenziswa ngokubanzi kwi:
Iipleyiti zeCeramic zesikrweqe somzimba (Ukhuseleko lweNqanaba III kunye ne-IV).
Ikhaka lemoto lomkhosi kunye nezicelo zamapolisa.
Ukhuseleko lwenqwelomoya kunye nehelikopta.
Kwiinkqubo ezihlanganisiweyo zekhaka, Iithayile ze-B ₄ C zidla ngokuxhaswa yi-fiber-reinforced polymers (umz., Kevlar okanye UHMWPE) ukufunxa amandla e-kinetic ashiyekileyo emva kokuba umaleko weceramic wophule iprojectile.
Kungakhathaliseki ukuqina kwayo okuphezulu, B AMANE C angaqalisa “amorphization” phantsi kwempembelelo yesantya esiphezulu, into ethintela ukusebenza kwayo ngokuchasene nemingcipheko yamandla aphezulu kakhulu, ukukhuthaza uphononongo oluphinda-phindayo lube luhlengahlengiso oludityanisiweyo kunye neeporcelains ezixutyiweyo.
5.2 Uyilo lweNyukliya kunye nokufunxwa kweNeutron
Phakathi kweyona misebenzi ibalulekileyo ye-boron carbide ihleli kulawulo lwe-nyukliya yereactor kunye nokhuseleko kunye neenkqubo zokhuseleko.
Ngenxa yokufunxwa okuphezulu kwe-neutron kunqamlezo lwe-isotope ye-¹⁰ B. (3837 izisele zeeneutron ezishushu), B EZINE C isetyenziswa kwi:
Iintonga zokulawula ii-reactors zamanzi ezinoxinzelelo (PWRs) kunye nezixhobo zamanzi abilayo (Ii-BWRs).
Iindawo ezikhuselayo zeNeutron.
Iinkqubo zokuvala imeko engxamisekileyo.
Ukukwazi ukufunxa i-neutron ngaphandle kokudumba okubalulekileyo okanye ukutshatyalaliswa phantsi kokukhanya kuyenza ibe yimveliso ethandwayo kwindawo zenyukliya..
Nangona kunjalo, Ukuveliswa kwerhasi ye-helium ukusuka kwi-¹⁰ B(n, a)⁷ Ukusabela kwe-Li kunokubangela uxinzelelo lwangaphakathi kunye ne-microcracking kunye nexesha, ifuna uyilo olulumkileyo kunye nokulandela umkhondo kwizicelo zexesha elide.
5.3 Amacandelo oShishino kunye noKunxitywa
Ngaphaya kokhuselo kunye neemarike zenyukliya, I-boron carbide ifumana ukusetyenziswa okugcweleyo kwizicelo zamashishini ezifuna ukuxhathisa okugqithisileyo:
Imilomo yokusikwa kwejet yamanzi kunye nokuqhunyiswa kwesanti.
I-Linings yeempompo kunye nokuvalwa kokuphatha i-slurries enzima.
Ukunciphisa izixhobo zeemveliso ezingenayo i-ferrous.
I-inertness yayo yeekhemikhali kunye nokuzinza kwe-thermal ivumela ukuba iqhube ngokuthembekileyo kwi-atmospheres enobutshaba yokulungisa imichiza apho izixhobo zentsimbi ngokuqinisekileyo ziya kuguga ngokukhawuleza..
6. Amathemba ekamva kunye neMida yoFundo loPhando
Ikamva le-boron carbide porcelains lixhomekeke ekoyiseni izithintelo zayo zangaphakathi– ngakumbi ukuqina okusezantsi kokuqhekeka kunye nokumelana ne-oxidation– ngesitayile esihlanganisiweyo esiphucukileyo kunye ne-nanostructuring.
Izalathiso zophando lwangoku zibandakanya:
Ukukhula kwe-B ₄ C-SiC, B ₄ C-TiB ₂, kunye ne-B EZINE C-CNT (carbon nanotube) iikhompawundi zokunyusa amandla kunye ne-thermal conductivity.
Ukuguqulwa komphezulu kunye nokugqiba izinto ezintsha zokunyusa ukuxhathisa i-oxidation.
Imveliso eyongezelelweyo (3D yoshicilelo) yeziko B EZINE C iinxalenye kusetyenziswa ijetting yebhinda kunye nezicwangciso ze-SPS.
Njengoko uphando lwezenzululwazi luhlala luza kuvela, I-boron carbide ibekwe ukuze idlale umsebenzi ongcono ngakumbi kwizinto ezintsha zesizukulwana esilandelayo, ukusuka kwiinxalenye zelori ze-hypersonic ukuya kwii-activators ze-nyukliya ezixubeneyo.
Ukushwankathela, I-boron carbide ceramics imele incopho yobuchule obuyiliweyo bemathiriyeli, ukudibanisa ukuqina okunzima, ubukhulu obuncitshisiweyo, kunye neepropati ezikhethekileyo zokuhlala zenyukliya kwinto enye.
Ngokuqhubela phambili okuqhubekayo kwi-synthesis, ukuphatha, kunye nesicelo, le nto emangalisayo iyaqhubeka nokutyhala imida yento enokwenzeka kuyilo olusebenza kakhulu.
Umthengisi
Advanced Ceramics yasekwa ngo-Oktobha 17, 2012, lishishini lobugcisa obuphezulu elizinikele kuphando nophuhliso, imveliso, ukuqhubekeka, ukuthengisa kunye neenkonzo zobugcisa bezixhobo ze-ceramic ezinxulumene neemveliso. Iimveliso zethu ziquka kodwa aziphelelanga kwiiMveliso zeCeramic zeBoron Carbide, IiMveliso zeCeramic zeBoron Nitride, Iimveliso zeCeramic zeSilicon Carbide, Iimveliso zeCeramic zeSilicon Nitride, IZirconium Dioxide yeeMveliso zeCeramic, njl. Ukuba unomdla, nceda uzive ukhululekile ukuqhagamshelana nathi.([email protected])
Iithegi: Boron Carbide, Boron Ceramic, Boron Carbide Ceramic
Onke amanqaku kunye nemifanekiso avela kwi-Intanethi. Ukuba kukho nayiphi na imiba ye-copyright, nceda uqhagamshelane nathi ngexesha lokucima.
Sibuze