Boron Carbide (B4C) ke ceramic e tšoarellang nako e telele e entsoeng ka Boron le carbon. Boron Carbide ke e 'ngoe ea lintho tse thata ka ho fetisisa tse tsejoang, e boemong ba boraro ka morao ho cubic Boron nitride le diamond. Ke thepa e kopanetsoeng e sebelisoang lits'ebetsong tse fapaneng tsa bohlokoa, ho kenyeletsoa lihlomo tsa tanka, li-bulletproof vests le phofshoana ea ho senya enjene. Ha e le hantle, ke thepa e ratoang bakeng sa mefuta e fapaneng ea lisebelisoa tsa indasteri. Sengoliloeng sena se fana ka kakaretso ea Boron Carbide le melemo ea eona.
Hantle-ntle Boron Carbide ke eng?
Boron Carbide ke motsoako oa bohlokoa oa lik'hemik'hale o nang le sebopeho sa kristale se tšoanang le li-boride tse thehiloeng ho icosahedral. Motsoako ona o ile oa sibolloa lekholong la leshome le metso e robong la lilemo e le sehlahisoa sa karabelo ea boride ea tšepe. E ne e sa tsejoe hore e na le foromo ea lik'hemik'hale ho fihlela lilemong tsa bo-1930, ha motsoako oa eona oa lik'hemik'hale o ne o hakanngoa hore ke B4C. X-ray crystallography ea ntho e bontša hore e na le sebopeho se rarahaneng haholo se entsoeng ka liketane tsa C-B-C le B12 icosahedra.
Boron Carbide e na le boima bo feteletseng (9.5–9.75 sekaleng sa Mohs), e tsitsitseng khahlanong le mahlaseli a ionizing, e hanyetsanang le tšebetso ea lik'hemik'hale, le lisebelisoa tse ntle tse sireletsang neutron. The Vickers hardness, elastic modulus, le ho robeha ha Boron Carbide li batla li tšoana le tsa daemane.
Ka lebaka la ho thatafala ho feteletseng, Boron Carbide e boetse e bitsoa "daemane e ntšo." E boetse e bonts'itsoe hore e na le thepa ea semiconducting, 'me lipalangoang tsa mofuta oa hopping li laola thepa ea eona ea elektroniki. Ke semiconductor ea mofuta oa p. Ka lebaka la boima ba eona bo feteletseng, e nkoa e le thepa ea ceramic e sa sebetseng, e etsang hore e lokele ho sebetsana le lintho tse ling tse thata haholo. Ntle le thepa ea eona e ntle ea mochini le matla a khoheli a tlase, e loketse ho etsa lihlomo tse bobebe.
Tlhahiso ea Boron Carbide Ceramics
Boron Carbide powder e hlahisoa khoebong ka ho kopanngoa (e leng ho akarelletsa ho fokotsa Boron anhydride (B2O3) ka carbon) kapa magnesiothermic reaction (e leng se akarelletsang ho etsa hore Boron anhydride e sebetsane le magnesium ha ho na le carbon black). Karabelo ea pele, sehlahisoa se etsa lesela le leholo le bōpehileng joaloka lehe bohareng ba mokelikeli. Sehlahisoa sena se bōpehileng joaloka lehe sea ntšoa, se siloa, ebe se siloa ka boholo bo loketseng ba lijo-thollo bakeng sa tšebeliso ea ho qetela.
Tabeng ea magnesiothermic reaction, stoichiometric Carbide e nang le granularity e tlase e fumanoa ka kotloloho, empa e na le litšila, ho kenyeletsoa ho fihla ho 2% ea graphite. Ka ha Boron Carbide e le motsoako o kopantsoeng ka kopanelo, ho thata ho sinter ntle le ho kenya mocheso le khatello ka nako e le 'ngoe. Ka lebaka lena, Boron Carbide hangata e etsoa libōpeho tse teteaneng ka ho hatella phofo e chesang, e hloekileng (limithara tse 2) mochesong o phahameng (2100–2200 °C) sebakeng se hloekileng kapa se sa tsitsang.
Mokhoa o mong oa ho hlahisa Boron Carbide ke ho cheka ho se na khatello ka mocheso o phahameng haholo (2300–2400 °C), e haufi le sebaka se qhibilihang sa Boron Carbide. Ho thusa ho fokotsa mocheso o hlokahalang bakeng sa densification nakong ea ts'ebetso ena, lithuso tsa sintering tse kang alumina, Cr, Co, Ni, le khalase li kenngoa motsoako oa phofo.
Lisebelisoa tsa Boron Carbide Ceramics
Boron Carbide e na le lisebelisoa tse ngata tse fapaneng.
Boron Carbide e sebelisoa e le ntho e qhekellang le e senyang.
Boron Carbide ka mofuta oa phofo e loketse hantle hore e sebelisoe e le ntho e hohlang le e laping e nang le sekhahla se phahameng sa ho ntša thepa ha e lokisa lintho tse thata haholo.
Boron Carbide e sebelisoa ho etsa li-nozzle tsa ceramic.
Boron Carbide e manganga haholo ho koaheloa, e leng se etsang hore e be sesebediswa se setle haholo bakeng sa ho qhomisa melomo ha e tjheswa. Esita le ha e sebelisoa le lisebelisoa tse matla haholo tsa ho qhomisatse kang corundum le silicon Carbide, matla a ho phatloha a lula a tšoana, ho na le ho apara ho fokolang, 'me li-nozzles li tšoarella haholoanyane.
Boron Carbide e sebelisoa e le thepa ea tšireletso ea ballistic.
Boron Carbide e fana ka tšireletso e bapisoang le ea tšepe ea lihlomo le aluminium oxide empa ka boima bo tlase haholo. Lisebelisoa tsa mehleng ea kajeno tsa sesole li khetholloa ke boima bo phahameng, matla a khatello, le modulus e phahameng ea elasticity, ho phaella ho boima bo tlaase. Boron Carbide e phahametse lisebelisoa tse ling kaofela bakeng sa sesebelisoa sena.
Boron Carbide e sebelisoa joalo ka mohanyi oa neutron.
Ho boenjineri, ntho ea bohlokoahali e monyang nyutrone ke B10, e sebelisoang e le Boron Carbide taolong ea nyutrone.
Sebopeho sa athomo sa boron se e etsa hore e be mohanyi o sebetsang oa neutron. Haholo-holo, isotope ea 10B, e teng hoo e ka bang 20% ea bongata ba tlhaho ea eona, e na le karolo e phahameng ea nyutlelie 'me e ka tšoara li-neutron tsa mocheso tse hlahisoang ke karabelo ea fission ea uranium.
Nuclear Grade Boron Carbide Disc Bakeng sa Neutron Absorption