Kev npaj thiab kev faib tawm ntawm cov pa roj carbon fiber ntau
Cov pa roj carbon fiber ntau tau siv dav hauv aerospace, tsheb, thiab lwm yam kev ua haujlwm siab vim lawv lub zog-rau-hnyav piv thiab siab nruj. Kev npaj thiab kev faib tawm ntawm cov fibers no koom nrog ntau cov txheej txheem nyuaj uas yuav tsum muaj cov cuab yeej tshwj xeeb thiab kev txawj ntse.
Kev npaj ntawm Carbon Fibers:
Cov pa roj carbon fibers feem ntau yog npaj los ntawm cov ntaub ntawv ua ntej, xws li polyacrylonitrile (PAN), suab, lossis rayon. Cov ntaub ntawv precursor tau hloov mus rau hauv fibers los ntawm cov txheej txheem hu ua pyrolysis, uas cuam tshuam cov khoom cua sov kom sov thaum tsis muaj oxygen.
PAN-raws li Carbon Fibers:
PAN-based carbon fibers yog cov khoom siv dav tshaj plaws ntawm carbon fibers vim lawv cov khoom zoo tshaj. Cov txheej txheem tsim khoom ntawm PAN-based carbon fibers koom nrog ntau theem, suav nrog oxidation, stabilization, thiab carbonization.
Thawj theem, oxidation, suav nrog cua sov PAN fibers hauv huab cua los txhim kho lawv cov thermal stability thiab tshem tawm cov impurities. Cov txheej txheem no tsim cov khoom hu ua oxidized PAN (OPAN), uas yog tom qab ntawd ua tiav los tsim kom ruaj khov PAN (SPAN).
Nyob rau theem thib ob, kev ruaj khov, SPAN fibers tau ua kom sov rau ib puag ncig 250 degree hauv qhov chaw tsis muaj zog kom ua rau muaj tshuaj lom neeg sib txuas thiab txhim kho cov fibers. Cov khoom uas tshwm sim yog hu ua carbon fiber precursor.
Finally, in the third stage, carbonization, the precursor fibers are heated to high temperatures (>1000 degree) thaum tsis muaj oxygen los hloov lawv mus rau carbon fibers.
Pitch-based Carbon Fibers:
Pitch-based carbon fibers yog npaj los ntawm cua sov roj av los yog thee tar pitch mus rau qhov kub thiab txias thaum tsis muaj huab cua. Tom qab ntawd cov khoom siv tau raug extruded rau hauv fibers thiab carbonized. Cov fibers no muaj cov cuab yeej zoo heev tab sis kim dua los tsim piv rau PAN-based carbon fibers.
Kev faib tawm ntawm Carbon Fibers:
Cov pa roj carbon fibers raug cais raws li lawv lub zog tensile thiab modulus. Lub zog tensile yog qhov siab tshaj plaws ntawm cov khoom siv tuaj yeem tiv taus ua ntej tawg, thaum lub modulus hais txog cov khoom tawv.
Cov txheej txheem kev faib tawm siv rau carbon fibers yog raws li tensile modulus thiab tau tsim los ntawm International Organization for Standardization (ISO). Tus txheej txheem ISO muab cov pa roj carbon fiber ntau rau hauv cov qib sib txawv, txhua qhov tshwj xeeb tensile modulus ranges.
Cov qib feem ntau ntawm carbon fibers yog:
- Standard modulus (SM): Tensile modulus ntawm 34-38 MSI.
- Intermediate modulus (IM): Tensile modulus ntawm 38-42 MSI.
- High modulus (HM): Tensile modulus ntawm 42-75 MSI.
- Ultra-high modulus (UHM): Tensile modulus ntawm 75-145 MSI.
Xaus:
Kev npaj thiab kev faib tawm ntawm cov pa roj carbon fiber ntau yuav tsum muaj kev paub tshwj xeeb thiab khoom siv. PAN-raws li carbon fibers yog hom siv dav tshaj plaws vim lawv cov khoom zoo tshaj plaws thiab kev ua haujlwm zoo. Cov pa roj carbon fibers tau muab cais raws li lawv lub zog tensile thiab modulus, nrog rau ntau qib uas muaj rau cov kev siv tshwj xeeb. Kev tshawb fawb tsis tu ncua thiab kev txhim kho hauv cov tshuab carbon fiber ntau yuav tsum ua kom muaj kev txhim kho ntxiv hauv lawv cov khoom thiab tus nqi qis, ua rau lawv nrov hauv ntau qhov kev lag luam.
