Date :2022-05-28  Kwakabva: Fiber Composites

Chimiro chelattice cheyakanaka graphite crystal ndeye hexagonal crystal system, inova yakawanda-layer yakatarisana chimiro inoumbwa nekabhoni maatomu mune nhanhatu-nhengo mhete network. Mumhete ine nhengo nhanhatu, maatomu ecarbon ari muchimiro chesp 2 hybrid

Basic structure

Iyo lattice chimiro cheyakanaka graphite crystal ndeye hexagonal crystal system, iyo inoumbwa nekabhoni maatomu anoumbwa nenhanhatu-nhengo ring network chimiro. Mumhete ine nhengo nhanhatu, maatomu ecarbon ari sp 2 hybridization iripo. MuSp2 hybridization, pane 1 2s electron uye 2 2p electron hybridization, ichiita matatu akaenzana o mabhondi akasimba, nhambwe yebhondi i0.1421nm, avhareji yesimba rebhondi i627kJ/mol uye makona ebhondi anoita 120 rimwe nerimwe.

Iwo akasara akachena 2p orbitals mundege imwe chete anoenderana nendege uko matatu o ma bond aripo, uye maN-bond emaatomu ecarbon anogadzira iyo N-bond anofanana kune imwe neimwe uye anopindirana kuita yakakura N. -bond; Maerekitironi asiri emunzvimbo ari pa n erekitironi anogona kufamba akasununguka anoenderana nendege, achiipa conductive properties. Vanogona kutora chiedza chinooneka, kuita graphite dema. Simba re van der Waals pakati pema graphite layers ishoma pane yevalence bond force mukati mezvikamu. Iyo nzvimbo pakati pematanho ndeye 0.3354nm, uye iyo bond simba i5.4kJ/mol. Iwo magirafu akaturikidzana akadzikiswa nehafu yehexagonal symmetry uye anodzokororwa mune imwe neimwe layer, achigadzira ABAB.

Chimiro [4], nekuchipa nekuzvigadzika uye kugona mukati memukati, sezvakaratidzwa muMufananidzo 2-5. Carbon fiber ndeye microcrystalline ibwe-inki zvinhu zvakawanikwa kubva kune organic fiber necarbonization uye graphitization.

Iyo microstructure yekabhoni fiber yakafanana neiyo yekugadzira graphite, inova yechimiro chepolycrystalline chaotic graphite. Musiyano kubva pachimiro chegraphite chiri mukududzirwa kusiri kwemaitiro uye kutenderera pakati peatomu layer (ona Mufananidzo 2-6). Iyo nhanhatu-element network covalent bond inosungwa muatomic layer ye - inonyanyoenderana nefiber axis. Naizvozvo, zvinogarotendwa kuti kabhoni faibha inoumbwa neyakakanganiswa graphite chimiro pamwe nekukwirira kwefiber axis, zvichikonzera yakanyanya axial tensile modulus. Iyo lamellar chimiro chegraphite ine yakakosha anisotropy, iyo inoita kuti zvimiro zvayo zvemuviri zviratidzewo anisotropy.

Zvivakwa uye kushandiswa kwekabhoni fiber

Carbon fiber inogona kukamurwa kuita filament, staple fiber, uye staple fiber. Iyo mechanical properties yakakamurwa kuva yakajairika mhando uye yakakwirira-kuita mhando. Iyo General carbon fiber simba ndeye 1000 MPa, iyo modulus inenge 10OGPa. High-performance carbon fiber yakakamurwa kuva yakakwira simba mhando (simba 2000MPa, modulus 250GPa) uye yakakwirira modhi (modulus pamusoro 300GPa). Simba rakakura kupfuura 4000MPa inonziwo Ultra-yakakwirira simba mhando; Avo vane modulus yakakura kupfuura 450GPa vanodaidzwa kuti emhando yepamusoro-soro. Nekuvandudzwa kweindasitiri yemuchadenga neyendege, simba rakakwirira uye yakakwira elongation kabhoni fiber yakaonekwa, uye kureba kwayo kwakakura kupfuura 2%. Iyo yakakura ndeye polypropylene ziso PAN-based carbon fiber. Carbon fiber ine yakakwira axial simba uye modulus, hapana inokambaira, yakanaka kuneta kuramba, chaiyo kupisa uye magetsi conductivity pakati peisina-simbi nesimbi, diki coefficient yekuwedzera kwemafuta, yakanaka corrosion kuramba, yakaderera fiber density, uye yakanaka X-ray kutapurirana. Zvisinei, kupikisa kwayo kunokanganisa kwakashata uye kuri nyore kukuvadza, oxidation inoitika pasi pekuita kweasidhi yakasimba, uye metal carbonization, carburization, uye electrochemical corrosion inoitika kana yasanganiswa nesimbi. Nekuda kweizvozvo, kabhoni faibha inofanirwa kugadziriswa pamusoro isati yashandiswa.