Yadda za a bambanta bambanci tsakanin pre-oxidation/carbonization/graphitization

PAN-tushen raw wayoyi suna buƙatar zama pre-oxidized, ƙananan zafin jiki carbonized, da babban zafin jiki carbonized don samar.carbon fibers, sa'an nan kuma graphitized don yin graphite zaruruwa. Zazzabi yakan kai daga 200 ℃ zuwa 2000-3000 ℃, wanda ke aiwatar da halayen daban-daban kuma ya samar da tsari daban-daban, wanda hakan yana da kaddarorin daban-daban.
1. Matakin pyrolysis:Pre-oxidation a cikin ɓangaren ƙananan zafin jiki, ƙarancin zafin jiki na carbonization a cikin ɓangaren zafi mai zafi.
Pre-oxidation arylation faruwa, tsawon kusan 100 minutes, zafin jiki na 200-300 ℃, da manufa shi ne zuwa thermoplastic PAN mikakke macromolecular sarkar a cikin wadanda ba filastik zafi-resistant trapezoidal tsarin, babban dauki ga macromolecular sarkar cyclization da intermolecular crosslinking, tare da saki da yawa pyrolysis. Ma'anar arylation gaba ɗaya shine 40-60%.
Ƙananan zafin jiki na carbonizationne kullum 300-800 ℃, yafi thermal fatattaka dauki, mafi yawa ta yin amfani da high-zazzabi lantarki makera waya dumama, da mataki samar da babban adadin shaye gas da kwalta,.
Halaye: Launi na fiber da aka riga aka yi da oxidized zai zama duhu, yawanci baƙar fata, amma har yanzu yana riƙe da ilimin halittar fiber, tsarin ciki ya sami wani nau'i na canje-canjen sinadarai, samuwar wasu ƙungiyoyi masu aiki masu dauke da iskar oxygen da tsarin haɗin giciye, ƙaddamar da harsashi na carbonization na gaba.
2. (High-zazzabi) matakin carbonization, shine pre-oxidation na precursor a cikin yanayin inert a high zafin jiki bazuwar, cirewa wanda ban da carbon heteroatoms (kamar oxygen, hydrogen, nitrogen, da dai sauransu), don haka da cewa carbonization a hankali, samuwar amorphous carbon ko microcrystalline carbon tsarin. Wannan tsari muhimmin mataki ne na samuwar kwarangwal din carbon. Yawan zafin jiki yana tsakanin 1000-1800 ℃, yawanci thermal condensation reaction, yawancin graphite heaters ana amfani dashi don dumama.
Halaye: Babban bangaren da carbonized abu ne carbon, tsarin shi ne mafi yawa amorphous carbon ko m graphite tsarin, ta lantarki watsin, inji Properties idan aka kwatanta da pre-oxidation samfurin yana da wani gagarumin karuwa.
3. Zane-zaneshine ƙarin maganin zafi na samfuran carbonization a yanayin zafi mafi girma don haɓaka tsarin carbon amorphous ko microcrystalline carbon zuwa tsarin kristal graphite mafi tsari. Ta hanyar aikin babban zafin jiki, ana sake tsara ƙwayoyin carbon don samar da tsarin Layer na lattice hexagonal tare da babban matakin daidaitawa, don haka yana inganta haɓakar wutar lantarki da thermal da ƙarfin injina na kayan.
Halaye: Samfurin da aka zana yana da tsarin graphite mai kristal sosai, wanda ke ba da ingantaccen ƙarfin lantarki da yanayin zafi, haka kuma yana da ƙayyadaddun ƙarfi da ƙayyadaddun modules. Alal misali, high-moduluscarbon fibersana samun su ta hanyar babban matakin graphitization.
Takamaiman matakai da buƙatun kayan aiki don pre-oxidation, carbonization da graphitization:
Pre-oxidation: za'ayi a cikin iska a yanayin zafi mai sarrafawa na 200-300 ° C. Ana buƙatar amfani da tashin hankali don rage raguwar fiber.
Carbonization: ana aiwatar da shi a cikin yanayi marar amfani tare da karuwa a hankali a yanayin zafi zuwa 1000-2000 ° C.
Zane-zane: ana yin shi a yanayin zafi mafi girma (2000-3000 ° C), yawanci a cikin injin daskarewa ko a cikin yanayi mara kyau.