Maitiro ekusiyanisa musiyano pakati pe pre-oxidation/carbonization/graphitization

PAN-yakavakirwa waya mbishi inoda kuve pre-oxidized, yakaderera-tembiricha carbonized, uye yakakwirira-tembiricha kabhoni kuti iumbe.carbon fibers, uyezve graphitized kugadzira graphite fibers. Iyo tembiricha inosvika kubva pa200 ℃ kusvika 2000-3000 ℃, iyo inoita maitiro akasiyana uye inoumba zvimiro zvakasiyana, izvo zvakare zvine zvimiro zvakasiyana.
1. Pyrolysis stage:Pre-oxidation mune yakaderera-tembiricha chikamu, yakaderera-tembiricha carbonization mune yakakwirira-tembiricha chikamu
Pre-oxidation arylation inoitika, kureba kweanenge maminetsi e100, tembiricha ye200-300 ℃, chinangwa ndeye thermoplastic PAN linear macromolecular chain mune isiri-yepurasitiki inodzivirira kupisa-inodzivirira trapezoidal chimiro, iyo huru yekuita kweiyo macromolecular cheni ye cyclization uye intermolecular kuburitswa kweakawanda kuburitsa uye kuburitsa ma molecule akawanda. Iyo arylation index inowanzoita 40-60%.
Low-temperature carbonization tembirichainowanzoita 300-800 ℃, kunyanya kupisa kwekuputika kwekuita, kunyanya kushandisa high-tembiricha yemagetsi echoto chekudziya waya, nhanho inoburitsa yakawanda yekubuda gasi netara,.
Hunhu: Rudzi rwefiber pre-oxidized richava rakasviba, kazhinji dema, asi richiramba richichengeta morphology yefiber, chimiro chemukati chakaita imwe dhigirii yekuchinja kwekemikari, kuumbwa kwenhamba yeakisijeni-ine mashandiro emapoka uye kuchinjika kwekubatanidza, kuisa hwaro hweiyo inotevera carbonization.
2. (High-temperature) carbonization stage, ndiyo pre-oxidation yeprecursor mumhepo inert pane yakakwirira tembiricha kuora, kubviswa kweiyo kuwedzera kune kabhoni heteroatoms (yakadai seoksijeni, hydrogen, nitrogen, nezvimwewo), kuitira kuti zvishoma nezvishoma carbonization, kuumbwa kweamorphous carbon kana microcrystalline carbon structure. Iyi nzira inhanho yakakosha mukuumbwa kwekabhoni skeleton. Tembiricha inowanzova pakati pe1000-1800 ℃, kunyanya thermal condensation reaction, mazhinji emagraphite heaters anoshandiswa kupisa.
Hunhu: Chinhu chikuru cheiyo carbonized zvinhu kabhoni, chimiro chakanyanya amorphous kabhoni kana chaotic graphite chimiro, yayo magetsi conductivity, mechanical properties ichienzaniswa nepre-oxidation chigadzirwa ine kuwedzera kukuru.
3. GraphitizationKuwedzera kupisa kurapa kwezvigadzirwa zvecarbonization pane tembiricha yepamusoro kusimudzira chimiro cheamorphous kabhoni kana microcrystalline kabhoni kune yakarongeka yakarongeka graphite crystal chimiro. Kuburikidza nekuita kwekupisa kwakanyanya, maatomu ekabhoni anorongwa patsva kuti aite hexagonal lattice layer ine yakakwira dhigirii yekumisikidza, nekudaro inovandudza zvakanyanya magetsi uye ekupisa conductivity uye simba remuchina wechinhu.
Hunhu: Iyo graphitized chigadzirwa ine yakanyanya crystalline graphite chimiro, iyo inopa yakanakisa magetsi uye yekupisa conductivity, pamwe nepamusoro yakananga simba uye chaiyo modulus. Somuenzaniso, high-moduluscarbon fibersinowanikwa kuburikidza nehuwandu hwepamusoro hwe graphitization.
Matanho chaiwo uye zvinodiwa zvemidziyo pre-oxidation, carbonization uye graphitization:
Pre-oxidation: inoitwa mumhepo pane inodzorwa tembiricha ye200-300 ° C. Tension inoda kuiswa kuderedza fiber shrinkage.
Carbonization: inoitwa mumhepo inert uye zvishoma nezvishoma kuwedzera kwekushisa kusvika 1000-2000 ° C.
Graphitization: inoitwa pane tembiricha yepamusoro (2000-3000 ° C), kazhinji muvacuum kana mumhepo inert.