Kev npaj cov txheej txheem ntawm cov khoom siv carbon fiber ntau

Txheej txheem cej luam ntawm Carbon-Carbon Composite Materials

Carbon / carbon (C / C) cov khoom sib xyawyog cov khoom siv carbon fiber reinforced composite nrog cov khoom zoo heev xws li lub zog siab thiab modulus, lub teeb tshwj xeeb lub ntiajteb txawj nqus, me me thermal expansion coefficient, corrosion kuj, thermal shock kuj, kev sib txhuam zoo, thiab tshuaj lom neeg ruaj khov. Nws yog ib hom tshiab ntawm ultra-siab kub sib xyaw khoom.

C / C cov khoom siv sib xyawyog ib qho zoo heev thermal qauv-functional integrated engineering khoom. Zoo li lwm cov ntaub ntawv sib xyaw ua haujlwm siab, nws yog cov qauv sib xyaw ua ke ntawm cov txheej txheem fiber ntau thiab cov theem pib. Qhov txawv yog tias ob qho tib si lub zog txhawb zog thiab theem pib yog tsim los ntawm cov pa roj carbon ntshiab nrog cov khoom tshwj xeeb.

Carbon / carbon composite cov ntaub ntawvFeem ntau yog ua los ntawm cov pa roj carbon monoxide, cov ntaub ntawv carbon, carbon fiber li qhov cuab lub zog, thiab vapor deposited carbon li matrix, tab sis nws tsuas muaj ib lub caij, uas yog carbon. Txhawm rau ua kom qhov ntom ntom, cov pa roj carbon tsim los ntawm carbonization yog impregnated nrog carbon lossis impregnated nrog resin (los yog asphalt), uas yog, carbon / carbon composite cov ntaub ntawv yog ua los ntawm peb cov ntaub ntawv carbon.

Manufacturing txheej txheem ntawm carbon-carbon composite cov ntaub ntawv

1) Kev xaiv ntawm carbon fiber

Kev xaiv cov pa roj carbon fiber ntau thiab cov qauv tsim ntawm fiber ntau fabrics yog lub hauv paus rau kev tsim khoomC / C sib xyaw. Cov khoom siv hluav taws xob thiab cov khoom siv thermophysical ntawm C / C composites tuaj yeem txiav txim siab los ntawm kev xaiv cov fiber ntau thiab cov ntaub qhwv cov ntaub ntawv, xws li xov paj bundled orientation, xov paj bundle spacing, xov paj ntim cov ntsiab lus, thiab lwm yam.

2) Kev npaj ntawm carbon fiber preform

Carbon fiber ntau preform yog hais txog ib qho dawb paug uas tau tsim rau hauv cov qauv tsim ntawm cov fiber ntau raws li cov khoom tsim thiab kev ua haujlwm yuav tsum tau ua kom ua tiav cov txheej txheem densification. Muaj peb txoj hauv kev ua haujlwm tseem ceeb rau cov txheej txheem preformed: soft weaving, hard weaving thiab soft thiab hard mix weaving. Cov txheej txheem tseem ceeb yog: qhuav yarn weaving, pre-impregnated rod pawg npaj, nplua weaving puncture, fiber ntau winding thiab peb-dimensional multi-directional weaving tag nrho. Tam sim no, lub ntsiab weaving txheej txheem siv nyob rau hauv C composite cov ntaub ntawv yog peb-dimensional zuag qhia tag nrho multi-directional weaving. Thaum lub sij hawm weaving, tag nrho cov woven fibers yog teem nyob rau hauv ib tug tej yam kev taw qhia. Txhua fiber ntau yog offset ntawm ib lub kaum ntse ntse raws nws tus kheej kev taw qhia thiab interwoven nrog ib leeg los tsim ib daim ntaub. Nws cov yam ntxwv yog tias nws tuaj yeem tsim peb-dimensional multi-directional tag nrho cov ntaub, uas tuaj yeem tswj qhov ntim cov ntsiab lus ntawm fibers hauv txhua qhov kev coj ntawm C / C cov khoom sib xyaw, kom cov khoom siv sib xyaw C / C tuaj yeem siv cov khoom tsim nyog. nyob rau hauv tag nrho cov lus qhia.

3) C / C densification txheej txheem

Cov degree thiab efficiency ntawm densification yog feem ntau cuam tshuam los ntawm cov qauv ntaub thiab cov txheej txheem tsis ntawm lub hauv paus khoom. Cov txheej txheem kev siv tam sim no suav nrog impregnation carbonization, tshuaj vapor deposition (CVD), tshuaj vapor infiltration (CVI), tshuaj kua kua deposition, pyrolysis thiab lwm txoj kev. Muaj ob hom txheej txheem txheej txheem: impregnation carbonization txheej txheem thiab tshuaj vapor infiltration txheej txheem.

Ua kua theem impregnation-carbonization

Cov txheej txheem ua kua theem impregnation yog qhov yooj yim hauv cov cuab yeej thiab muaj kev siv dav, yog li cov txheej txheem ua kua theem impregnation yog ib txoj hauv kev tseem ceeb rau kev npaj C / C cov ntaub ntawv sib xyaw. Nws yog rau raus lub preform ua los ntawm carbon fiber rau hauv cov kua impregnant, thiab ua rau impregnant siab nkag mus rau hauv lub voids ntawm lub preform los ntawm pressurization, thiab ces los ntawm ib tug series ntawm cov txheej txheem xws li kho, carbonization, thiab graphitization, thaum kawg tau txais.C / C cov ntaub ntawv sib xyaw. Nws qhov tsis zoo yog tias nws yuav siv sij hawm rov qab impregnation thiab carbonization cycles kom ua tiav cov kev xav tau ceev. Cov muaj pes tsawg leeg thiab cov qauv ntawm impregnant nyob rau hauv cov kua theem impregnation txoj kev yog ib qho tseem ceeb heev. Nws tsis tsuas yog cuam tshuam rau kev ua haujlwm densification, tab sis kuj cuam tshuam rau cov khoom siv thiab lub cev ntawm cov khoom. Txhim kho cov pa roj carbonization ntawm impregnant thiab txo cov viscosity ntawm impregnant ib txwm yog ib qho ntawm cov teeb meem tseem ceeb uas yuav tsum tau daws nyob rau hauv kev npaj cov ntaub ntawv C / C los ntawm cov kua theem impregnation. Lub siab viscosity thiab qis carbonization tawm los ntawm impregnant yog ib qho tseem ceeb ntawm cov khoom siv C/C composite tus nqi siab. Kev txhim kho kev ua tau zoo ntawm impregnant tuaj yeem tsis tsuas yog txhim kho kev tsim khoom ntawm C / C cov ntaub ntawv sib xyaw thiab txo lawv cov nqi, tab sis kuj txhim kho ntau yam khoom ntawm C / C cov ntaub ntawv sib xyaw. Kev kho oxidation ntawm C / C cov ntaub ntawv sib xyaw Cov pa roj carbon fiber pib oxidize ntawm 360 ° C hauv huab cua. Graphite fiber yog me ntsis zoo dua li carbon fiber, thiab nws oxidation kub pib oxidize ntawm 420 ° C. oxidation kub ntawm C / C cov ntaub ntawv sib xyaw yog li 450 ° C. C / C cov ntaub ntawv sib xyaw yog yooj yim heev rau oxidize nyob rau hauv high-temperature oxidative cua, thiab oxidation tus nqi nce sai nrog qhov kub thiab txias. Yog tias tsis muaj kev tiv thaiv oxidation, kev siv cov khoom siv C / C mus sij hawm ntev nyob rau hauv qhov chaw kub kub oxidative yuav inevitably ua rau muaj kev puas tsuaj loj. Yog li ntawd, kev kho cov tshuaj tiv thaiv oxidation ntawm C / C cov ntaub ntawv sib xyaw tau dhau los ua ib feem tseem ceeb ntawm nws txoj kev npaj. Los ntawm qhov kev xav ntawm cov cuab yeej siv tshuaj tiv thaiv oxidation, nws tuaj yeem muab faib ua cov cuab yeej siv tshuaj tiv thaiv oxidation thiab tiv thaiv oxidation txheej tshuab.

Chemical Vapor Phase

Chemical vapor deposition (CVD lossis CVI) yog tso cov pa roj carbon ncaj qha rau hauv qhov hws ntawm qhov khoob kom ua tiav lub hom phiaj ntawm kev sau cov pores thiab nce qhov ntom. Cov carbon deposited yog ib qho yooj yim rau graphitize, thiab muaj lub cev zoo compatibility nrog cov fiber. Nws yuav tsis ntsws thaum re-carbonization zoo li txoj kev impregnation, thiab lub cev thiab txhua yam khoom ntawm txoj kev no zoo dua. Txawm li cas los xij, thaum lub sij hawm CVD txheej txheem, yog tias cov pa roj carbon tso rau ntawm qhov chaw ntawm qhov khoob, nws yuav tiv thaiv cov roj los ntawm diffusing mus rau hauv qhov pores. Cov pa roj carbon deposited ntawm qhov chaw yuav tsum tau muab tshem tawm mechanically thiab ces ib tug tshiab puag ncig ntawm deposition yuav tsum tau nqa tawm. Rau cov khoom tuab, CVD txoj kev kuj muaj qee qhov nyuaj, thiab lub voj voog ntawm txoj kev no kuj ntev heev.