Thaum tib neeg hnov 'cobalt alloy casting qhov chaw', lub koom haum tam sim ntawd feem ntau yog 'kev ua haujlwm siab', 'aerospace', lossis 'kev cog lus kho mob'. Qhov ntawd tsis yog qhov tsis ncaj ncees lawm, tab sis nws yog qhov kev nkag siab saum npoo av uas glosses dhau qhov kev muaj tiag ntawm kev ua cov khoom no. Qhov kev sib tw tiag tiag tsis yog nyob rau hauv cov ntawv hlau tshwj xeeb; Nws yog nyob rau hauv kev tswj cov kev hloov ntawm ib tug molten, reactive puddle ntawm hlau mus rau ib tug dimensionally ruaj khov, tsis muaj qhov tsis xws luag uas yuav ciaj sia nyob rau hauv ib tug turbine los yog ib tug tib neeg lub cev. Ntau tus xav tias yog tias koj tuaj yeem nrum hlau, koj tuaj yeem nrum cobalt alloys. Qhov kev xav ntawd tau raug nqi ntau dua li ob peb lub khw muag nyiaj ntau.
Lub Alloy tsis yog ib qho qauv xwb, Nws yog tus cwj pwm
Ua hauj lwm nrog cobalt-chromium alloys, zoo li cov qib CoCrMo, yog ib zaj lus qhia ntawm kev txo hwj chim. Koj tab tom cuam tshuam nrog cov khoom siv uas muaj qhov siab kawg nkaus melting point thiab lub siab tsis zoo los tsim cov oxides ruaj khov. Cov cobalt hlau casting txheej txheem, tshwj xeeb tshaj yog peev casting uas peb siv ntau, dhau los ua ib txoj kev nruj nreem ntawm qhov kub, pwm preheat, thiab pouring ceev. Ob peb degrees tawm ntawm pwm preheat, thiab koj tau txais mistruns. qeeb dhau ntawm lub ncuav, thiab koj tau txias kaw. nrawm dhau, thiab koj ntxiab roj lossis erode lub plhaub ceramic. Nws tsis yog ib daim ntawv qhia koj ua raws; nws yog ib qho tshuaj tiv thaiv koj sim xav txog thiab tswj.
Kuv nco qab ib pawg rau cov roj turbine foob ntu ob peb xyoos dhau los. Cov chemistry tau zoo tag nrho, cov ntoo siv quav ciab yog flawless. Tab sis hnub ntawd peb muaj ib tug txiv neej tshiab ntawm lub cub tawg. Nws ua raws li tus txheej txheem txheej txheem rau nickel-based superalloy peb kuj khiav. Qhov tshwm sim? Cov hlau 'pancaked' nyob rau hauv pwm - nws poob nws fluidity sai heev. Cov khoom zoo li tsis pom kev zoo, tab sis X-ray tau pom tias muaj qhov porosity hauv cov ntu tuab. Tag nrho cov cua sov tau muab pov tseg. Hnub ntawd yog hnub uas pab neeg no tiag tiag internalized tias cobalt alloys tsis zam txim. Lawv solidification ntau thiab thermal conductivity yog cov tsiaj nyaum tshwj xeeb. Koj siv tsis tau generic casting txoj cai.
Qhov no yog qhov kev paub ntev, zoo li 30+ xyoo ntawm lub khw zoo li QSY, dhau los ua qhov pom tseeb. Nws tsis yog hais txog kev ua khawv koob; nws yog hais txog muaj ib tug sib sib zog nqus, yuav luag intuitive lub tsev qiv ntawv ntawm ua-thiab-npaum rau txawv geometry. Koj kawm tau hais tias ib tug nyias-walled valve tivthaiv xav tau ib tug radically sib txawv rooj vag thiab nce lub tswv yim piv rau ib tug bulky coj phaj, txawm tias lawv yog los ntawm tib qib alloy. Kev paub yog nyob rau hauv cov qauv engineering ntev ua ntej cov hlau puas tau yaj.
Plhaub Pwm Casting: Precision nrog daim tawv nqaij Ceramic
Rau complex, siab ncaj ncees cobalt alloy qhov chaw, plhaub pwm casting-ib hom peev casting-feem ntau yog tib txoj kev siv tau. Qhov saum npoo tiav thiab qhov tseeb qhov tseeb yog unmatched los ntawm xuab zeb casting. Tab sis lub plhaub ceramic nws tus kheej yog qhov hloov pauv tseem ceeb. Cobalt alloys yog reactive. Yog tias lub plhaub cov ntaub ntawv los yog cov khoom siv refractory muaj cov impurities uas tuaj yeem txo cov pa oxygen hauv zos ntawm qhov kub siab, koj tau txais qhov tshwm sim hu ua 'hlau-pwm cov tshuaj tiv thaiv'. Nws tsim ib qho nyuaj, nkig, feem ntau paug txheej txheej ntawm lub casting uas yog npau suav phem rau tshuab tawm thiab tuaj yeem nkaum cov kab nrib pleb.
Peb tau siv ntau lub hlis hu rau hauv peb lub plhaub system rau kev ua haujlwm cobalt. Nws yog ib qho kev sib xyaw ua ke, tab sis qhov tseem ceeb yog siv high-purity alumina thiab zirconia refractories nrog silica-free binder system. Lub voj voog ziab thiab tua hluav taws yog kev ua phem - qeeb qeeb mus rau qhov kub siab heev kom hlawv tawm cov organic thiab sinter lub plhaub rau hauv lub thawv muaj zog, tsis muaj zog. Lub voj voog hluav taws xob nrawm ua rau lub plhaub tsis muaj zog uas tuaj yeem tawg thaum lub sij hawm nchuav lossis, qhov phem dua, tsim cov microcracks uas cia cov hlau nkag mus, ua rau lub ntsej muag puas. Kuv tau pom cov khoom tawm tuaj zoo li lawv muaj hwj txwv ceramic. Qhov ntawd yog tag nrho cov rework, los yog seem.
Kev koom tes nrog lub plhaub chav tsev yog qhov tseem ceeb. Ntawm QSY, qhov casting thiab machining yog nyob rau hauv ib lub ru tsev, uas yuav pab tau. Cov machinists uas tom qab ntawd yuav tsum tau txiav cov khoom nyuaj no yuav yws tam sim yog tias lub plhaub txheej txheem tawm, vim tias lawv cov cuab yeej lub neej poob qis thaum lawv tsoo cov txheej txheem reactive. Qhov kev tawm tswv yim sab hauv yog invaluable. Nws yuam cov foundry sab kom muaj qhov teeb meem txij thaum pib mus txog rau thaum xaus, tsis yog kom txog thaum ib feem yog shaken tawm ntawm cov xuab zeb.
Qhov twg CNC Machining nkag mus sib tham
Tsis muaj cobalt hlau casting ib feem yog tiag tiag 'net-shape'. Koj ib txwm xav tau machining, thiab qhov no yog qhov twg cov roj hmab ua tau raws li txoj kev. Cobalt alloys yog qhov tsis yooj yim rau tshuab. Lawv ua hauj lwm-harden sai, lawv yog abrasive, thiab lawv tuav lub zog ntawm kub kub. Ib qho kev ua haujlwm tsis zoo tuaj yeem muaj kev ntxhov siab los yog micro-kawg uas yuav ua rau tsis ua haujlwm ntxov ntxov. Qhov no yog vim li cas kev ua haujlwm sib xyaw ua ke yog qhov tseem ceeb heev.
Lub as-cam khwb cia muaj nplai, qhov rooj kaw lus, thiab cov khoom siv ntau dhau (cov khoom 'cov khoom'). Thawj kauj ruam yog feem ntau tshem tawm lub rooj vag nrog lub log txiav tawm-tshwj xeeb ya mus txhua qhov chaw. Tom qab ntawd nws mus rau CNC zeb los yog tshuab dhos. Kev xaiv cuab yeej yog txhua yam. Koj xav tau cov cuab yeej nruj, qib siab carbide, qee zaum txawm tias ceramic lossis CBN ntxig rau kev ua tiav. Coolant siab thiab ntim yog tsis-negotiable; koj yuav tsum tau dej nyab qhov txiav kom tswj tau cov cua sov thiab ntxuav cov chips. Ib tug nti uas recuts instantly ruins lub insert.
Peb machined ib series ntawm cobalt-raws li alloy rooj zaum rau hnyav-service li qub. Lub tolerances ntawm lub sealing nto yog nyob rau hauv lub microns. Qhov kev sib tw yog tias qhov casting, tom qab kev kho cua sov, muaj me ntsis distortion, unpredictable distortion. Peb cov programmers CNC yuav tsum tau tsim nyob rau hauv kev sojntsuam niaj hnub mus rau 'daim ntawv qhia' ntawm qhov tseeb geometry nyob rau hauv lub fixture ua ntej qhov kawg tiav. Nws ntxiv sijhawm, tab sis nws yog tib txoj kev los lav lub foob. Hom kev hloov kho machining no tsis nyob hauv phau ntawv; nws yog yug los ntawm scrapping ob peb kim castings thiab xam seb yog vim li cas.
Kev kho cua sov: Qhov Kev Ua Si ntsiag to-Hloov pauv
Qhov no tej zaum yuav yog qhov feem ntau overlooked nam. Cov khoom ntawm cobalt alloy casting yog tsim nyob rau hauv lub tshav kub kho rauv, tsis yog lub qhov cub casting. Kev kho mob, kev laus-cov voj voog no txhais tau tias qhov kawg microstructure, carbide faib, thiab cov khoom siv kho tshuab. Tau txais nws yuam kev, thiab koj muaj ib feem nrog txoj cai chemistry uas ua tau zoo li khib nyiab.
Qhov teeb meem yog sib xws. Ib qho loj, tuab-section thiab me me, nyias ib qho los ntawm tib lub tshav kub tsis tuaj yeem pom tib lub sijhawm-kub profile. Qhov tuab ntawm cov tub ntxhais yuav tsis ncav cuag qhov kub thiab txias, tawm hauv cov theem uas tsis xav tau. Peb kawm qhov no txoj kev nyuaj nrog ib tug khiav ntawm phais implant prototypes. Lub zog tensile thiab qaug zog lub neej yog qhov tsis sib xws ntawm ib feem. Tus neeg ua txhaum yog lub cub tawg qhov thermal uniformity thiab peb cov qauv thauj khoom. Peb yuav tsum tau nqis peev rau hauv qhov cub ua kom zoo nrog ntau thaj chaw tswj thiab nruj tswj kev tswj hwm cov txheej txheem. Tam sim no, rau cov khoom tseem ceeb, peb txawm siv cov thermocouples embedded nyob rau hauv cov khoom fij tseg nyob rau hauv lub load los xyuas cov thermal keeb kwm.
Nws yog ib kauj ruam kim, tab sis nws yog qhov cais cov khoom lag luam los ntawm kev ntseeg siab tiv thaiv. Koj tsis tuaj yeem kuaj xyuas microstructure rau hauv ib feem; Koj yuav tsum ua nws hauv. Qhov kev muaj peev xwm rov qab no yog qhov ua rau tus neeg xa khoom zoo li QSY ntseeg tau rau kev kho mob thiab kev ua haujlwm hauv aerospace, qhov twg cov ntaub ntawv (cov ntawv kho cua sov) tseem ceeb npaum li qhov nws tus kheej.
Kev Ntsuas Tiag: Kev Ntsuam Xyuas Tsis Ua Haujlwm thiab Kev Ua Haujlwm
Qhov tseeb xeem ntawm kev txawj ntse nyob rau hauv cobalt alloy casting qhov chaw tsis yog thawj tsab xov xwm zoo meej. Nws yog koj li cas rau cov uas ua tsis tau. Peb muaj ib qho kev tivthaiv rau lub twj tso kua mis tshuaj uas ua tsis tau rau qaug zog tom qab ob peb puas teev. Cov neeg siv khoom tau, nkag siab, chim siab. Tom qab-mortem koom nrog ntu ntu, ua SEM / EDS tsom xam ntawm qhov tawg. Peb pom ib pawg ntawm cov khoom tsis yog xim hlau-zoo li ib qho ntawm cov khoom tawg ntawm lub plhaub los yog cov slag particle-uas ua raws li qhov chaw pib tawg.
Qhov ntawd ua rau kev tshuaj xyuas tag nrho: kev txhim kho peb cov hlau pom thaum lub sij hawm nchuav (peb hloov mus rau lub tshuab ua npuas ncauj hauv qhov rooj), kev tshuaj xyuas nruj dua ntawm cov plhaub ceramic ua ntej sib dhos, thiab siv ntau zaus slag skimming thaum melting. Qhov 'kho' tsis yog ib qho kev ua; nws yog ib tug systemic nruj tswj. Tom ntej no batch khiav tsis muaj teeb meem. Qhov kev ua tsis tiav ntawd, ua rau mob siab heev, tej zaum ua tau ntau dua los txhim kho peb cov txheej txheem ntau dua li kaum ob txoj haujlwm ua tiav.
Qhov no yog sab unglamorous. Nws tsis yog hais txog kev muag lub sizzle ntawm 'aerospace-qib'. Nws yog hais txog kev muaj lub chaw kuaj metallurgical, cov txheej txheem zoo, thiab kab lis kev cai los rhuav tshem koj tus kheej txoj haujlwm, nrhiav lub hauv paus ua haujlwm, thiab hloov koj txoj haujlwm li cas. Qhov ntawd yog 30 xyoo ntawm kev hais lus. Nws yog qhov tsub zuj zuj ntawm cov kev kho me me, nyuaj-yeej uas tsim cov txheej txheem txhim khu kev qha rau kev ua qee yam raws li qhov xav tau. cobalt-raws li alloy casting. Thaum kawg, ib feem tsuas yog zoo li qhov tsis muaj zog txuas hauv cov saw ntev heev, los ntawm cov qauv siv quav ciab mus rau qhov kawg tshuaj ntsuam xyuas.
