Koj pom 'MIM' tossed nyob ib ncig ntawm ntau niaj hnub no, feem ntau raws li ib lo lus buzz rau 'complex, pheej yig qhov chaw.' Qhov ntawd yog thawj qhov kev xav tsis zoo. Nws tsis yog khawv koob, thiab nws yeej tsis yog ib txwm pheej yig. Zaj dab neeg tiag tiag ntawm hlau txhaj molding txheej txheem pib ntev ua ntej pwm kaw, nyob rau hauv qhov nkig, theem tseem ceeb ntawm feedstock. Ua qhov tsis ncaj ncees lawm, thiab tsis muaj dab tsi ntxiv.
Lub Feedstock Dance: Ntau Art than Science
Txhua leej txhua tus tham txog molding los yog sintering, tab sis lub plawv ntawm ib tug txhim khu kev qha MIM lag luam yog feedstock homogeneity. Peb tsis yog tsuas yog sib xyaw hlau hmoov thiab binder; peb tab tom tsim ib qho kev sib txuam, flowable compound. Qhov ratio yog txhua yam. Ntau dhau binder? Koj tau txais slumping thiab distortion thaum debinding. tsawg dhau? Koj tsis tuaj yeem sau cov ntu nyias. Kuv tau pom cov khoom siv los ntawm cov chaw muag khoom sib txawv, txawm tias muaj cov specs tib yam, coj txawv txawv txawv. Nws tsis yog hais txog cov hmoov D50 xwb; nws yog qhov particle zoo faib. Spherical hmoov los ntawm cov roj atomization ntws zoo dua, paub meej, tab sis cov duab sib npaug tuaj yeem ua rau qhov kawg ntom ntom yog tias koj tsis ceev faj nrog sintering profiles.
Thaum ntxov, peb muaj ib qhov project rau ib qho kev phais me me, ib feem nrog ib tug ntoo khaub lig-section uas mus ntawm 2 hli mus rau 0.5 hli. Peb siv tus qauv 316L feedstock. Cov khoom tau zoo tag nrho ntawm cov pwm. Tom qab ntawd tuaj catalytic debinding. Cov ntu nyias xwb... ploj lawm. Tsis melted, tab sis structurally ua tsis tau tejyam. Tus binder tshem tawm tus nqi yog nruj heev rau qhov sib txawv loj. Zaj lus qhia? Koj qhov kev tsim cov khoom noj khoom haus yuav tsum raug kho tsis yog rau cov khoom siv xwb, tab sis rau qhov seem ntawm cov geometry. Ib qho me me-haum-tag nrho cov hmoov / binder blend yog ib daim ntawv qhia rau kev mob siab. Koj xav tau tus khub uas nkag siab qhov no ntawm qib granular, ib tus neeg nyiam Qingdao Qiangsenyuan Technology Co., Ltd. (QSY). Nrog rau lawv lub xyoo caum hauv precision casting, lawv nkag siab qhov tseem ceeb ntawm cov khoom coj cwj pwm nyob rau hauv thermal kev nyuaj siab, ib tug mindset uas txhais ncaj qha rau kev tswj MIM feedstock thiab sintering.
Thiab lub binder system nws tus kheej - uas yog tag nrho lwm lub ntiaj teb no. Wax-polymer, dej-soluble, catalytic-txhua tawm nws cov ntiv tes rau ntawm qhov. Catalytic (siv nitric acid vapor) yog ceev tab sis tuaj yeem tua qee yam alloys. Thermal debinding qeeb tab sis maj mam. Qhov kev xaiv ntawm no dictates koj lub sijhawm rau lub cub tawg, koj qhov kev tuav, thiab koj qhov tsis xws luag. Nws yog lub hauv paus kev xaiv uas koj ua ua ntej koj txawm tsim lub cuab yeej.
Sintering: Qhov twg Khawv koob (thiab Shrinkage) Tiag tiag tshwm sim
Qhov no yog lub sij hawm ua-los-tawm. Koj tau txais koj qhov 'xim av' - tsis yooj yim, tag nrho cov hlua khi thiab pob txha pob txha. Lub voj voog ntawm lub cub tawg yog qhov uas nws dhau los ua hlau. Lub shrinkage yog kwv yees, feem ntau nyob ib ncig ntawm 15-20%, tab sis nws yeej tsis zoo kawg nkaus isotropic. Ib qhov ntev, tiaj tus tuaj yeem hloov pauv yog tias tsis txhawb nqa kom raug ntawm cov khoom siv. Peb ib zaug khiav ib batch ntawm connector daim hlau. Dimensional kam rau ua tau nruj ntawm lub qhov mounting. Peb ntaus qhov theoretical sintered ntom, tab sis lub qhov ovalized los ntawm ob peb microns. Vim li cas? Lub qhov cub cua muaj me ntsis gradient. Cov seem ntawm sab laug ntawm txoj siv tau pom qhov sib txawv ntawm qhov kub thiab txias dua li ntawm sab xis.
Kev tswj huab cua yog txhua yam. Hydrogen, argon, nqus tsev, los yog tawg ammonia. Rau cov hlau tsis muaj steel, koj xav tau qhov chaw zoo kom txo tau qhov chaw huv si yam tsis muaj carburization. Ib qho dej me me, me ntsis ntawm cov pa nkag, thiab koj tau txais ib qho crusty, sintered ib feem uas yog nkig. Nws tsis yog ib txwm pom ntawm qhov muag liab qab. Peb muaj ib pawg ntawm 17-4 PH qhov chaw uas dhau qhov kev tshuaj xyuas qhov muag thiab txawm tias qhov ntsuas qhov loj me. Tab sis nyob rau hauv daim ntawv thov, lawv ua tsis tau tejyam nyob rau hauv qaug zog. Metallography pom cov oxide suav nrog nyob rau hauv ib thaj tsam ntawm cov qoob loo - cov kab ntawm huab cua thaum lub sij hawm tseem ceeb nruab nrab ntawm sintering.
Qhov no yog qhov uas qhov kev paub ntawm ib tug foundry tiag tiag qhia. Ib lub tuam txhab zoo li QSY, uas tau ua haujlwm rau ntau tshaj 30 xyoo hauv lub plhaub thiab peev casting nrog alloys xws li cov qauv hlau mus rau npib tsib xee-based superalloys, nkag siab txog kev ua thermal hauv lawv cov pob txha. Qhov kev paub ntawm qhov tshwj xeeb alloys coj li cas ntawm qhov kub thiab txias, yuav ua li cas tswj cov huab cua kom tiv thaiv kev sib kis, yog ncaj qha hloov mus thiab muaj nuj nqis rau lub hlau txhaj molding txheej txheem. Lawv paub tias sintering tsis yog 'kub nws' xwb; nws yog ib tug tswj metamorphosis.
Cov cuab yeej cuab tam thiab kev ua haujlwm thib ob
Cov neeg xav tias MIM tshem tawm kev ua haujlwm. Nws minimizes nws. Koj tseem yuav luag ib txwm xav tau kev pabcuam thib ob. EDM rau cov yam ntxwv uas tsis tuaj yeem raug molded, zoo li undercuts lossis zoo kawg nkaus square sab hauv fab. Lub teeb CNC machining rau qhov tseem ceeb sealing nto los yog xov. Qee zaum, kev ua haujlwm coining tom qab sinter kom muaj tseeb txog qhov loj me. Lub ntxiab yog tsim MIM ib feem zoo li nws yuav yog qhov kawg-zoo li ib feem. Koj yuav tsum tsim rau tus txheej txheem. Cov radii dav dav, cov phab ntsa tuab tuab yog qhov ua tau, cov kaum sab xis - cov no tsis yog cov lus qhia.
Kuv nco qab ib lub cuab yeej rau lub koob yees duab vaj tse. Tus tsim qauv xav tau ib qho zoo nkauj, ntse aesthetic ntug. Zero radius. Peb sim nws. Cov khoom noj yuav tsis ua kom tsis tu ncua, thiab cov ces kaum yuav nti thaum tawm los yog tuav hauv lub xeev xim av. Peb yuav tsum rov qab mus, ntxiv ib lub vojvoog 0.1 hli. Nws tsis pom nyob rau hauv cov khoom kawg tab sis ua rau cov khoom tsim tau. Cov cuab yeej nws tus kheej yog lwm cov tsiaj nyaum. Nws yog kev txhaj tshuaj molding cuab yeej, yog li nws xav tau polish, zoo vents, qhov rooj zoo. Tab sis koj nyob nraum abrading nws nrog hlau hmoov. Hnav ntawm cov ces kaum thiab cov rooj vag yog siab dua nrog cov yas. Koj yuav tsum tau npaj rau kev saib xyuas ntawd.
Thiab qhov no yog kev sib koom ua ke nrog tus muab kev pabcuam tag nrho. Yog tias koj saib QSY lub peev xwm, lawv sau CNC machining txoj cai nrog rau lawv qhov tshwj xeeb casting. Qhov ntawd yog qhov tseem ceeb. Lawv tuaj yeem nqa cov sintered MIM ib feem thiab hauv tsev, tshuab qhov tseem ceeb ntawm cov ntaub ntawv los yog laum lub qhov ntoo khaub lig uas tsis tuaj yeem pwm. Qhov kev sib xyaw ntsug ntawd tswj tau qhov zoo thiab tus nqi. Koj tsis tau xa cov khoom tawg yooj yim mus rau lwm lub khw muag khoom, pheej hmoo rau kev puas tsuaj.
Material Realities: Nws tsis yog rau Stainless xwb
Cov ntaub ntawv hauv phau ntawv yog 316L, 17-4PH, cov pa roj carbon steel. Tab sis cov ntawv thov nthuav yog nyob rau hauv cov khoom txawv. Peb tau ua haujlwm nrog tungsten hnyav alloys rau ntsuas qhov hnyav thiab txawm tias qee qhov kev sim nrog titanium. Ti MIM yog npau suav phem ntawm nws tus kheej-koj sintering hauv lub tshuab nqus tsev siab, thiab cov hmoov yog kim thiab pyrophoric los daws. Kev them nyiaj yog complex, lub teeb yuag biomedical implants. Tab sis tus nqi tawm los ... yog qhov kev sib tw.
Qhov no ua tau zoo kawg nkaus nrog cov ntaub ntawv pov thawj ntawm tus kws tshaj lij zoo li qhov tau hais ua ntej. Lawv cov kev paub nrog cobalt-based thiab npib tsib xee-raws li alloys hauv peev casting yog ib qho khoom muaj nqis loj. Cov alloys no muaj lawv tus kheej sintering quirks-kua theem sintering, activated sintering-thiab paub lawv cov metallurgy dav dav los ntawm lwm cov txheej txheem muab lub taub hau pib. Cov hlau txhaj molding txheej txheem rau ib qho kev tivthaiv superalloy tsis yog ib qho khoom sib txawv; nws yog ib tug txawv kiag li lub tswv yim ntawm densification thiab microstructure txoj kev loj hlob.
Koj kuj tsis tuaj yeem tsis quav ntsej cov hlau nplaum mos, xws li Fe-Si lossis Fe-Ni. Sintering cov no kom ua tiav ob qho tib si siab ceev thiab cov khoom sib nqus kom raug yog kev taug kev nruj. Kub kub heev, koj poob cov khoom; tsawg dhau, koj muaj porosity. Nws yog cov ntawv thov niche uas MIM tiag tiag ci, tsis yog ua lwm yam khoom siv uas tuaj yeem raug ntaus.
Thaum MIM Tsis yog Cov Lus Teb
Qhov no tej zaum yuav yog ntu tseem ceeb tshaj plaws. MIM yog qhov zoo heev rau cov ntim siab, cov duab geometry nyuaj, qhov nruab nrab-siab ntev. Tab sis yog tias koj qhov yooj yim - ib qho yooj yim spacer, ib tug ncaj pas nrig - mus nrog machining los yog stamping. Yog tias koj xav tau ultra-siab tensile lub zog los yog cuam tshuam toughness as-cam khwb cia, saib cov peev casting. Yog tias koj xav tau tus qauv ib-tawm, 3D hlau luam ntawv yuav zoo dua, txawm tias muaj teeb meem saum npoo.
Lub crossover nrog peev casting yog qhov nthuav tshwj xeeb. Rau qhov loj dua (hais tias, tshaj 100-150 grams) los yog qhov chaw uas xav tau tsis muaj porosity nyob rau hauv ib qho tseem ceeb, ib tug zoo-tsim peev casting tej zaum yuav txhim khu kev qha thiab nqi-zoo. Ib lub tuam txhab uas muaj ob qho tib si, xws li QSY, tuaj yeem muab kev pom zoo rau koj. Lawv tsis sim yuam kom muaj txheej txheem; lawv tuaj yeem saib koj cov ntawv luam tawm thiab hais tias, Rau qhov txheej txheem no thiab ntim, MIM yuav txuag koj 30% ntawm cov nqi tsev, lossis Qhov kab noj hniav sab hauv no tob dhau, cia peb saib lub plhaub pwm casting hloov.
Peb kawm qhov nyuaj no. Ib tug neeg tau hais rau MIM rau qhov loj, kuj yooj yim bracket. Cov cuab yeej yog loj thiab kim, sintering distortion yog ib qho kev sib ntaus sib tua, thiab tus nqi ntawm cov khoom yog siab dua li lwm yam fabricated. Peb yuav tsum tau thawb rov qab. Cov txheej txheem yog ib qho cuab yeej, tsis yog kev ntseeg. Nws txoj kev zoo nkauj yog nyob rau hauv nws qhov tshwj xeeb qab zib: noj ntau ntau ntawm cov khoom siv thiab sib sau ua ke rau hauv ib qho, deburred, npaj txhij-rau-siv daim hlau uas tawm ntawm lub cub tawg zoo li nws tau loj hlob, tsis ua. Thaum nws ua haujlwm, nws yog qhov ci ntsa iab engineering. Thaum nws raug yuam, nws tsuas yog ib qho teeb meem kim.
