Kev ceev faj tseem ceeb thaum kho cua sov ntawm Titanium Phaj Cheebtsam
1. Kev tswj huab cua: Kev txhawj xeeb tseem ceeb
Titanium cov tshuaj muaj zog heev ntawm qhov kub siab ua rau huab cua tswj qhov tseem ceeb tshaj plaws hauv kev kho cua sov. Tsis zoo li cov hlau, titanium tsis tuaj yeem tiv thaiv los ntawm cov pa cua xws li hydrogen, carbon monoxide, lossis tawg ammonia, vim nws nkag siab nrog cov pa roj.
Lub tshuab nqus tsev vacuum (nyiam dua):Kev kho cua sov lub tshuab nqus tsev yog qhov kev xaiv zoo tshaj plaws rau titanium phaj Cheebtsam. Nws muab qib siab tshaj plaws ntawm kev tiv thaiv los ntawm kev tshem tawm tag nrho cov pa cua hauv huab cua tsis yog tsuas yog hloov lawv. Rau lub tshuab nqus tsev annealing, lub siab ua hauj lwm feem ntau yuav tsum tau khaws cia tsis pub tsawg tshaj 2 × 10⁻³ Pa kom tsis txhob nqus qhov chaw corrosion tshwm sim los ntawm kev kub siab heev. Qee daim ntawv thov siv siab -purity argon rau kev tswj lub siab ib nrab.
Inert Gas Atmosphere:Thaum lub tshuab nqus tsev tsis muaj, siab -purity argon lossis helium cua tuaj yeem muab kev tiv thaiv txaus. Txawm li cas los xij, txawm tias cov pa roj tsis zoo no yuav tsum tau ua kom huv huv heev - tsis muaj dej noo thiab kab tsis huv - los tiv thaiv kev kis kab mob. Argon purity tsis tsawg tshaj li 99.99% feem ntau yuav tsum tau, txawm tias siab dua purity yuav tsim nyog rau kev siv aerospace tseem ceeb.
Electrically Heated Furnaces:Cov tshuab hluav taws xob tau pom zoo siv roj ntau dua - cov hluav taws xob hluav taws xob. Roj- cov hluav taws kub hnyiab tau tsim cov khoom siv hluav taws xob uas muaj hydrogen thiab noo noo, uas tuaj yeem ua paug rau titanium. Yog tias cov roj- yuav tsum tau siv lub tshuab hluav taws xob, qhov cua yuav tsum tau tswj kom tsis muaj zog lossis oxidizing me ntsis-tsis txhob txo qis, vim tias txo cov huab cua txhawb kev tsim hydrogen.
Rauv Purging:Furnaces yav tas los siv rau kev kho cua sov ntawm cov hlau yuav tsum tau purged kom huv si rau ob peb teev nrog cov roj npaj ua ntej ua titanium. Cov hydrogen residual los ntawm tawg ammonia los yog lwm yam hlau-kev kho cua sov tuaj yeem nyob hauv cov refractory crevices thiab paug titanium qhov chaw. Huab cua- ntws tawm ntawm qhov ntim ntau thiab lub sijhawm (piv txwv li, 150 cubic feet ib feeb rau 4 teev) raug pom zoo rau huab cua- tshuab cua sov.
2. Tiv thaiv Alpha Case tsim
Cov ntaub ntawv Alpha yog ib qho nkig, oxygen-enriched nto txheej uas tsim thaum titanium yog rhuab tshaj li ntawm 590-620℃nyob rau hauv lub xub ntiag ntawm oxygen. Cov txheej no yog ib qho nyuaj heev thiab abrasive, txo cov ductility thiab qaug zog zog thaum ua rau cov machining tom ntej.
Minimization Strategies:
Siv lub sijhawm ua cua sov luv tshaj plaws ntawm qhov kub kom tsis txhob muaj cov pa oxygen
Tswj qhov kub thiab txias, raws li oxidation tus nqi nce exponentially nrog kub
Kev kho lub tshuab nqus tsev tshem tawm cov ntaub ntawv alpha tsim tag nrho, tsis tas yuav tsum tau tshaj tawm - kho qhov chaw tshem tawm
Kev Cai tshem tawm:Yog tias cov ntaub ntawv alpha tshwm sim thaum kho cua sov hauv qhov tsis yog - lub tshuab nqus tsev lossis cov cua tsis huv, cov txheej txheem tsis huv yuav tsum raug tshem tawm tag nrho ua ntej cov khoom siv nkag mus. Txoj kev tshem tawm muaj xws li:
Tshuab dhos: Sib sib zog nqus txiav yog pom zoo los txhim kho lub neej ntawm cov cuab yeej, raws li cov ntaub ntawv alpha yog abrasive heev
Tshuaj pickling: HF-HNO₃ cov kev daws teeb meem tuaj yeem ua rau cov txheej txheem tawg
Abrasive txoj kev: Sandblasting los yog sib tsoo (raws li los ntawm pickling kom tiav tshem tawm)
Kev pov thawj ntawm kev tshem tawm tiav tuaj yeem ua tiav los ntawm kev etching nrog ammonium bifluoride tov - xim grey qhia tias cov ntaub ntawv alpha tseem tshuav, thaum grey tsaus qhia tias cov hlau huv huv.
3. Hydrogen Embrittlement tiv thaiv
Hydrogen paug yog tshwj xeeb yog txaus ntshai rau titanium alloys vim nws diffuses sai heev los ntawm cov hlau lattice, muaj feem xyuam rau tag nrho cov tivthaiv es tsis yog tsuas yog nto. Cov ntsiab lus hydrogen tshaj 150 ppm tuaj yeem ua rau qis -kub embrittlement los ntawm kev tsim hydride.
Kev tiv thaiv:
Xyuas kom cov cua sov cua sov zoo kawg nkaus qhuav; noo noo dissociates ntawm qhov kub thiab txias los tsim hydrogen thiab oxygen
Zam tsis txhob muaj roj, roj, thiab hydrocarbon cov pa paug ntawm qhov chaw thiab qhov cub tawg, vim tias tsis tiav combustion ua rau hydrogen
Khaws oxidizing lossis nruab nrab cua; txo cov huab cua txhawb nqa hydrogen nqus
Siv dej deionized rau kev ntxuav ua ntej kev kho cua sov; Cov kais dej zoo tib yam muaj cov chlorides thiab fluorides uas tuaj yeem ua rau muaj kab mob
Kev tshem tawm Hydrogen:Yog tias kuaj pom muaj kab mob hydrogen (ntawm lub tshuab nqus tsev fusion), kev kho dehydrogenation yuav tsum tau ua. Cua sov ntawm 705-815℃(1300-1500℃F) hauv lub tshuab nqus tsev ntawm ib micron lossis tsawg dua tuaj yeem txo cov ntsiab lus hydrogen. Tus nqi tshem tawm yog nyob ntawm cov khoom thickness, geometry, lub sij hawm, thiab kub. Cov hlau thiab lub cub tawg yuav tsum huv si thiab oxide-dawb rau dehydrogenation zoo.
4. Nto huv huv thiab tshem tawm cov kab mob
Ua ntej kev kho cua sov, titanium phaj Cheebtsam yuav tsum tau ua tib zoo ntxuav kom tshem tawm tag nrho cov kab mob saum npoo uas tuaj yeem ua rau degradation:
Txwv tsis pub muaj kab mob:
Cov ntiv tes: Cov roj hauv lub cev muaj cov tshuaj chlorides thiab lwm cov tshuaj uas tuaj yeem ua rau muaj kev ntxhov siab corrosion
Chlorinated kuab tshuaj: Txawm tias cov khoom seem los ntawm cov tshuaj ntxuav tuaj yeem ua rau muaj kev ntxhov siab corrosion saum toj no kwv yees li 230℃(450℃F)
Hydrocarbons: Roj thiab roj yog cov ua rau embrittlement thaum kho cua sov
Anhydrous methanol: Ua rau muaj kev ntxhov siab corrosion tawg hauv titanium alloys; Yog hais tias methanol yuav tsum tau siv, nws yuav tsum tau diluted 50:50 nrog dej deionized, tab sis ntau manufacturers zam nws tag nrho.
Hydrofluoric acid thiab concentrated muaj zog acids: Cov no hnyav heev corrode titanium thiab yuav tsum tau nruj me ntsis zam
Txoj kev ntxuav kom pom zoo:
Nitric acid{0}}raws li los yog alkaline tshuaj ntxuav
Isopropanol ua lwm yam organic hnyav (tsis ua rau muaj kev ntxhov siab corrosion)
Deionized dej yaug tom qab txhua qhov kev ua haujlwm tu
Xyuas kom tseeb tias cov piv txwv uas tau ntxuav hauv cov kua qaub da dej qhia tias tsis muaj hydrogen tuaj
5. Kub thiab sijhawm tswj
Kev tswj qhov kub thiab txias yog qhov tseem ceeb vim tias muaj zog ntawm kev daws qhov kub thiab txias ntawm metallurgy thiab cov khoom kawg ntawm titanium alloys:
Recrystallization annealing: Feem ntau ua tau ntawm kwv yees li 730℃rau Ti-6Al-4V
Kev nyuaj siab nyem annealing: Feem ntau ua ntawm 500-650 degree
Kev kho mob: Kev xaiv kub nyob ntawm qhov tshwj xeeb alloy muaj pes tsawg leeg thiab xav tau microstructure; sab laj-cov ntaub ntawv tshwj xeeb
Soak lub sij hawm ntawm qhov kub thiab txias yuav tsum tau txo kom tsis txhob:
Kev loj hlob ntau dhau ntawm cov nplej, uas txo qhov toughness thiab ductility
Deep oxygen diffusion thiab tuab alpha case tsim
Hydrogen pickup los ntawm kab mob atmospheric kab mob
Distortion ntawm nyias phaj seem
Qhov kub tsis sib xws thoob plaws hauv lub cub tawg chamber yog qhov tseem ceeb rau cov khoom siv phaj kom ntseeg tau tias microstructure zoo ib yam thiab cov khoom siv tshuab thoob plaws tag nrho.
6. Tshaj tawm -Kev kho cua sov
Oxide Film Assessment:Tom qab kev kho cua sov hauv inert gas los yog lub tshuab nqus tsev, cov xim oxide xim qhia tias muaj kab mob:
Lub teeb daj oxide zaj duab xis: Tej zaum yuav ua tau yam tsis muaj kev tshem tawm
Lub teeb xiav, xiav, lossis grey oxide zaj duab xis: Yuav tsum tau muab tshem tawm raws li specifications
Qhov yuav tsum tau ua kom txias:Rau lub tshuab nqus tsev sov-cov khoom siv kho, cua txias hauv qab 200℃ua ntej raug rau qhov chaw nyob ib puag ncig tau pom zoo los ntawm qee cov qauv hauv aerospace kom txo qis thermal shock thiab oxidation nto.
Mechanical Testing:Kev kho cua sov ua haujlwm yuav tsum raug txheeb xyuas los ntawm cov kev ntsuas tsim nyog es tsis yog kev sim hardness ib leeg, vim tias kev sib raug zoo ntawm lub zog thiab hardness hauv titanium alloys tsis zoo. Cov qauv kuaj yuav raug txiav los ntawm cov qauv neeg sawv cev lossis cov nyiaj tso cai thev naus laus zis ntawm qhov chaw.
7. Kev txiav txim siab tshwj xeeb rau nyias phaj thiab daim ntawv
Titanium phaj thiab daim ntawv Cheebtsam muaj cov kev cov nyom tshwj xeeb:
Distortion tswj: Cov ntu nyias nyias yuav ua rau warping thaum cua sov thiab txias; Kev kho kom zoo thiab cov cua sov tsis sib xws yog qhov tseem ceeb
Caij nplooj ntoos hlav-rov qab: Titanium qhov qis qis ntawm elasticity thiab siab zog ua rau lub caij nplooj ntoos hlav tseem ceeb - rov qab thaum lub caij txias; kub sib sau tej zaum yuav nyiam rau cov duab complex
Kev kub ceev / txias: Nyias daim hlau cua sov thiab txias sai sai, yuav tsum tau lub sij hawm meej kom ua tau raws li qhov xav tau microstructure yam tsis muaj kev loj hlob ntau dhau los yog qhov seem seem
Qhov chaw saum npoo-rau- qhov piv ntawm qhov ntim: Qhov sib piv ntau dua ua rau muaj kev cuam tshuam rau atmospheric paug, ua rau huab cua tswj qhov tseem ceeb tshaj
