Titanium Alloy Melting Technology: VAR, EB thiab Plasma Hearth txheej txheem
Nov 05, 2024
Melting yog cov kauj ruam uas txiav txim siab qhov huv, chemistry thiab cov qauv kev sib xws ntawm txhua yam khoom titanium ua rau hauv qab. Titanium tsis tuaj yeem yaj nyob rau hauv kev sib cuag nrog cov pa refractories, nws absorbs oxygen, nitrogen thiab hydrogen nkag siab tshaj li ntawm 400 degrees Celsius, thiab nws melting point nyob ze 1668 degrees Celsius yog siab txaus uas alloying ntxiv ntawm molybdenum, vanadium los yog chromium yuav tsum tau qhia yam tsis tsim kev sib cais los yog unmelted hais. Niaj hnub nimno melting tshuab yog qhov tseem ceeb ntawm cov lus teb rau peb qhov kev txwv, thiab cov kev tsim kho tshiab tau piav qhia hauv qab no yog cov uas tau hloov pauv kev ua lag luam.
Vim li cas Titanium Melting txawv
Tsis muaj refractory contact:molten titanium txo cov oxides feem ntau, yog li melting yog nqa tawm hauv dej -coj tooj liab crucibles los yog hearths nyob rau hauv lub tshuab nqus tsev los yog siab - purity inert gas.
Gas rhiab heev:oxygen thiab nitrogen stabilize lub alpha theem thiab embrittle cov hlau, thaum hydrogen ua porosity; cov huab cua thiab cov khoom siv huv huv yuav tsum tau tswj ua ke.
High melting point ntxiv:cov ntsiab lus xws li molybdenum thiab vanadium yaj zoo saum titanium, yog li lawv tau ntxiv los ua cov alloys los yog nias compacts ntau dua li cov hlau ntshiab.
Nqus Arc Remelting Nrog Direct Ntxiv ntawm High Melting Point Metals
Nyob rau hauv lub tshuab nqus tsev arc remelting, ib tug consumable electrode yog yaj los ntawm ib tug ncaj qha tam sim no arc nyob rau hauv lub nqus tsev vacuum rau hauv dej -coj pwm txias. Qhov nyuaj classic yog ntxiv cov hlau refractory. Yog hais tias cov ntshiab molybdenum los yog vanadium poob rau hauv lub pas dej ua ke, cov hais tuaj yeem tog, yaj tsis tiav thiab tawm hauv cov kev sib txuam siab uas muaj sia nyob txhua qhov kev khiav dej num.
Kev txhim kho yog ntxiv cov ntsiab lus no ua aluminium-vanadium lossis aluminium-molybdenum master alloys, los yog raws li nias thiab sintered compacts sib xyaw rau hauv cov electrode, thiab kho cov txheej txheem melting kom lub pas dej sib sib zog nqus txaus kom yaj cov khoom ntxiv tab sis tsis sib sib zog nqus kom lawv sib cais. Xaiv qhov tseeb arc tam sim no, qhov sib txawv thiab yaj tus nqi tsim cov ingots uas nws muaj pes tsawg leeg ua tau raws li qhov yuav tsum tau ua piv nrog cov qauv, tsis yog - cais cov qauv. Txoj hauv kev no yog qhov tso cai rau titanium alloys xws li Qib 5 (UNS R56400) los ua rau ntawm kev lag luam nplai nrog cov chemistry txhim khu kev qha.
Restriking Arc thiab Multi-Stage Melting
Cov txheej txheem txwv arc nyob rau sab saum toj ntawm lub ingot. Es tsis txhob hloov lub arc tawm ntawm lub zog tag nrho, lub hwj chim tau nqis los thaum lub arc yog restruck thiab cov electrode yog rho tawm maj mam. Sab saum toj ntawm lub ingot nyob twj ywm kua ntev txaus los pub lub solidification contraction, uas shortens lub shrinkage yeeb nkab, txo spongy porosity thiab txhim kho yield. Restriking kuj homogenises lub sab saum toj ntawm lub ingot, qhov twg segregation yuav txwv tsis pub mloog.
Cov qib tseem ceeb yog yaj ob lossis peb zaug. Thawj qhov dhau los tsim cov chemistry, qhov thib ob refines qauv thiab disperses segregation, thiab qhov thib peb tswj cov roj cov ntsiab lus thiab kev faib ua ke. Txhua qhov dhau los yog qhov kev tshwm sim khov tshiab uas rhuav tshem cov qauv dhau los.
Electron Beam thiab Plasma Hearth Melting
Lub tshuab cua txias melting tshem tawm cov khoom siv uas nqus arc remelting tsis tuaj yeem. Feedstock yog yaj nyob rau hauv dej-coj tooj liab hearth, qhov twg cov khoom ntom ntom xws li tungsten carbide cov cuab yeej fragments nyob rau hauv lub pob txha taub hau thiab cov khoom tsis tshua muaj xws li titanium nitride ntab thiab raug kaw. Cov kua refined ces ntws mus rau hauv pwm los yog mus rau hauv ib tug casting.
Electron beam txias hearth melting:high vacuum, excellent for removing high density inclusions and volatile impurities, with precise control of superheat and evaporation.
Plasma arc melting:ua haujlwm nyob rau hauv inert gas ntawm siab dua, zam lub nqus evaporation ntawm alloying ntsiab thiab tuav loj npaum li cas ntawm recycled seem.
Ob qho txheej txheem feem ntau yog siv los ua thawj theem ntawm ob -theem txoj hauv kev: hearth melting rau kev huv, ua raws li lub tshuab nqus tsev arc remelting rau lub suab, cais tawm - dawb zaum kawg ingot.
Induction Skull Melting thiab Cold Crucible Practice
Induction skull melting siv cov dej segmented -coj tooj liab crucible thiab alternating magnetic teb. Lub pob txha taub hau nyias nyias ntawm tib lub alloy tiv thaiv lub crucible, yog li cov yaj tsis kov tooj liab. Lub zog nplawm kev ua haujlwm ntawm thaj chaw muab tshuaj lom neeg zoo sib xws, uas haum rau cov alloys nrog cov ntsiab lus hnyav thiab cov cua sov me me xws li peev castings thiab ze ntawm cov khoom sib txuas. Qhov kev txwv yog nplai: induction pob txha taub hau melting feem ntau yog siv rau cov cua sov ntawm ob peb puas kilograms es tsis yog ntau-tonne ingots.
Cov chav kawm suav nrog thiab lawv tswj tau li cas
| Chav kawm | Yam khoom | Tswj txoj kev |
| High density inclusions | Tungsten carbide cov cuab yeej fragments, refractory hlau hais | Txias hearth melting, huv si seem txoj cai, kev tshuaj ntsuam |
| Tsawg ceev suav nrog | Titanium nitride, oxygen - nplua nuj alpha hais | Hearth melting, ceev faj electrode tsim, ultrasonic kuaj |
| Gas porosity | Hydrogen, noo noo, paug daim txhuam cev | Nqus melting, qhuav feedstock, tswj cua |
| Segregation bands | Yooj yim tawg ntawm hnyav ntxiv | Master alloys, raug yaj tus nqi, ntxiv remelt passes |
Melt Quality thiab cov qauv qab nws
Ingot zoo yog txhais los ntawm cov qauv khoom raws li: ASTM B265 rau phaj, ntawv thiab sawb, ASTM B338 rau welded thiab seamless raj rau condensers thiab tshav kub exchangers, ASTM B348 rau bar thiab billet, thiab AMS thiab ISO 5832 series rau aerospace thiab cog qib. Txhua yam ntawm cov no hais txog lub suab nrov, kev txwv chemistry thiab kev soj ntsuam xyuas uas lub khw muag khoom yuav tsum xa, thiab cov neeg yuav khoom xav tau txoj kev melting kom tshaj tawm rau ntawm daim ntawv pov thawj ntau dua li qhov xav tau.
FAQ
Q: Vim li cas titanium melted hauv lub tshuab nqus tsev?
Vim tias molten titanium absorbs oxygen, nitrogen thiab hydrogen thiab txo cov refractory oxides. Lub tshuab nqus tsev los yog siab -purity inert gas nrog dej-coj copper crucibles ua kom cov yaj ntawm ob qhov chaw paug.
Q: Cov ntsiab lus zoo li molybdenum ntxiv rau titanium yaj li cas?
Raws li tus tswv alloys los yog pressed compacts blended rau hauv consumable electrode, nrog rau ib tug melting kev pab cuam xaiv ces cov ntxiv dissolve tag nrho tsis sinking thiab tsim high density inclusions.
Q: Dab tsi txwv qhov arc ua tiav?
Nws ua rau sab saum toj ntawm cov kua ingot thaum lub yaj tiav, uas ua rau qhov kawg contraction, ua kom cov yeeb nkab shrinkage, txo cov spongy porosity thiab txhim kho usable ingot yield.
Q: Thaum twg txias hearth melting nyiam dua lub tshuab nqus tsev arc remelting?
Thaum kev huv huv yog qhov tseem ceeb. Electron beam or plasma hearth melting traps both high and low density inclusions that vacuum arc remelting can carry through, and it handles recycled scrap and large feedstock well.
Q: Yuav tsum muaj pes tsawg lub melting passes rau qhov tseem ceeb?
Ob los yog peb qhov kev hla yog ib txwm muaj rau aerospace, kev kho mob thiab kub exchanger raj. Tus naj npawb tseeb yog teem los ntawm cov khoom specification thiab los ntawm kev huv ntawm cov khoom noj, tsis yog los ntawm txoj cai thoob ntiaj teb.
Q: Puas ntxiv melting hloov cov chemistry ntawm cov hlau?
Nws refines thiab homogenises chemistry es tsis hloov nws. Cov ntsiab lus tsis muaj zog tuaj yeem poob rau hauv lub tshuab nqus tsev electron beam melting, uas yog vim li cas qhov kev pab cuam yaj tau tsim nyog rau txhua qhov hlau thiab qhov kub thiab txias.
