Puas yog kev kho kev ntxhov siab xav tau tom qab luam ntawv pwm?

Ib, Txoj kev uas residual stress forms thiab cov txaus ntshai nws yuav ua tau
1. Muaj ntau yam kev nyuaj siab
Muaj peb hom kev hloov pauv uas ua rau muaj kev ntxhov siab thaum lub sij hawm pwm luam ntawv:
Cov txheej txheem tsis sib txawv: Yog tias lub zog laser, scanning ceev, thiab txheej txheej tsis raug teeb tsa kom raug, cov nqi ntawm cov khaubncaws sab nraud povtseg tuaj yeem sib txawv, uas tuaj yeem ua rau interlayer shear stress. Piv txwv li, thaum 3D luam ntawv yees duab- kho ceramics, kev hloov hauv txheej tuab (50-100 μm) thiab tsis txaus UV raug tuaj yeem ua rau muaj kev ntxhov siab interlayer, uas tuaj yeem ua rau tsis muaj zirconia scaffolds tawg ntawm tus nqi txog li 18%.
Kev txwv ntawm cov khoom siv: Thaum luam ntawv nrog hlau hmoov txaj melting (PBF), cua txias sai ua rau cov nplej tsis sib xws, siab - ntom nti dislocations hauv qee qhov chaw, thiab micro stresses. Piv txwv li, qhov kev ntxhov siab nyob hauv qhov tsis kho H13 pwm hlau uas tau luam tawm 3D yuav siab li 30% mus rau 50% ntawm cov khoom siv zog.
Tshem tawm cov qauv kev txhawb nqa thiab polishing qhov chaw yog cov piv txwv ntawm kev tshaj tawm - cov haujlwm ua haujlwm uas yuav ntxiv cov khoom siv tshuab ntxiv. Piv txwv li, yog tias cov pwm tsis muaj kev ntxhov siab- tau tso siab tom qab ua cov txheej txheem, qhov quenching deformation tuaj yeem nce 40% mus rau 60%.
2. Kev ntxhov siab tuaj yeem ua rau muaj kev phom sij ntau yam
Yog tias qhov kev ntxhov siab seem tsis raug daws zoo, nws yuav ua rau muaj teeb meem hauv qab no:
Dimensional instability: Thaum muaj kev ntxhov siab tawm, cov pwm warps thiab hloov cov duab, nrog qhov tseeb sib txawv ntawm ntau tshaj ± 80 μ m, uas yog qhov phem dua li cov qauv kev kho mob qib pwm (± 50 μ m).
Kev ua tau zoo degradation: Microcracks yuav tsim nyob rau hauv qhov chaw muaj kev ntxhov siab, uas txo qis qaug zog thiab cuam tshuam tsis kam. Piv txwv li, yog tias 3D- luam tawm alumina hluav taws xob substrate tsis yog annealed, cov hlau txheej tawm ntawm tus nqi ntawm 12% thiab cov insulating kuj hloov los ntawm ± 15%.
Lub neej lwj: Kev ntxhov siab superposition ua rau kev sib kis ntawm kev qaug zog tawg thaum lub sijhawm thauj khoom, txiav lub neej ntawm pwm los ntawm 50% mus rau 70%. Piv txwv li, tom qab 100,000 lub voj voog ntawm kev thauj khoom, qhov tawg ntawm kev nthuav tawm ntawm unannealed 3D luam tawm pwm hlau yog peb zaug sai dua li ntawm qhov chaw annealed.
2, Kev xav tau kev ntxhov siab: pov thawj los ntawm kev xav mus rau kev xyaum
1. Theoretical foundation: Qhov kev sib txuas ntawm kev daws kev ntxhov siab thiab kev ua haujlwm zoo dua
Thermodynamic lossis mechanical operations yog siv los kho kev ntxhov siab kom txav cov atoms nyob ib ncig ntawm cov khoom, txo qis dislocation ceev, thiab tshem tawm ntawm kev ntxhov siab. Qhov tseem ceeb tshaj plaws ntawm nws yog:
Kho microstructure: Cov txheej txheem annealing tuaj yeem kaw microcracks (ntev<50 μm) that form during sintering, which makes the material 2% to 3% denser. For instance, after annealing at 1150 °C, the microcrack closure rate of 3D printed zirconia parts goes from 90% to 420MPa, and the bending strength goes from 350MPa to 420MPa.
Kev txhim kho qhov ruaj khov ntawm qhov ntev: Qhov qis me me ntawm cov yas deformation (feem ntau tsawg dua 0.5%) uas tshwm sim thaum muaj kev ntxhov siab tso tawm tuaj yeem tiv thaiv kev cuam tshuam sai ntawm qhov tshwm sim thaum cov khoom siv dua. Piv txwv li, qhov tseeb qhov tseeb ntawm zirconia kho hniav cog tau nce los ntawm ± 80 μ m rau ± 30 μ m tom qab annealing, uas yog raws li ISO 13356 tus qauv kho mob.
Kev txhim kho machining kev ua tau zoo txhais tau tias txo qhov tawv tawv thiab qhov seem ntawm tensile kev nyuaj siab, nrog rau kev txo qis kev co thiab cov cuab yeej hnav thoob plaws hauv cov txheej txheem txiav. Piv txwv li, tom qab kev sib tsoo, cov hlau tuag yog kev ntxhov siab -relieved ntawm 260-315 degree, uas txo cov kev ntxhov siab ntawm qhov chaw los ntawm 40% mus rau 65% thiab ua ob npaug rau lub neej ntawm cov cuab yeej.
2. Tiag - piv txwv hauv ntiaj teb: tus qauv ua tiav rau kev siv hauv kev lag luam
Lub tuam txhab kho mob ua 3D- luam tawm zirconia implants los ntawm kev siv "UV curing molding → degreasing → sintering → annealing (1150℃rwb thaiv tsev rau 3 teev, cua sov 5℃/ h, txias 5℃/ h)" txheej txheem nyob rau hauv lub tshav pob ntawm ceramic pwm. Tus nqi tawg tau poob qis los ntawm 18% mus rau 3%, qhov qaug zog tiv thaiv tau nce los ntawm 25%, thiab cov batch pass tus nqi tau nce los ntawm 75% mus rau 96%.
Lub tuam txhab hluav taws xob tau ua 3D luam ntawv txhuas oxide hluav taws xob hauv cov hlau pwm los ntawm "sintering ua raws li kev sib tsoo (tuav ntawm 1300℃rau 4 teev, cua sov ntawm 10℃/ h, thiab txias ntawm 10℃/ h). Cov hlau txheej detachment tus nqi tau nqis mus rau 2%, thiab cov rwb thaiv tsev tiv thaiv kev hloov pauv tau qis dua mus rau ± 5%, uas ua tau raws li cov qauv kev ruaj ntseg siab.
Pwm nrog cov qauv nyuaj: Rau qhov tsis tu ncua, xws li kev txhawb nqa ntxeem tau, cov txheej txheem xws li cov cua sov ua kom sov (600℃rwb thaiv tsev rau 1 teev, 750℃rwb thaiv tsev rau 2 teev) thiab gradient txias (5-10℃/ h) tau ua haujlwm kom tau txais kev ntxhov siab thiab tsis txhob tawg los ntawm cov cua sov hauv zos.
3, Xaiv ib txoj hauv kev thiab kev ua kom zoo dua qub yog ib feem ntawm txoj kev kho kev ntxhov siab.
1. Txoj kev kho cua sov: kev tswj xyuas meej ntawm cov txheej txheem tseem ceeb
Annealing los txo kev ntxhov siab: Kub lub pwm kom qis dua Ac ₁ (piv txwv li, 500–650℃) thiab khaws cia rau 2-4 teev. Ces cia nws txias me ntsis. Nws ua haujlwm nrog cov pwm steel, aluminium alloy pwm, thiab ntau dua, thiab nws tuaj yeem tshem tawm ntau tshaj 80% ntawm qhov seem seem.
Kev kho lub sijhawm: Txhawb kom muaj kev ntxhov siab los ntawm kev laus los ntawm ntuj tsim (chav kub cia) lossis kev laus laus (100-200℃rwb thaiv tsev), uas yog qhov zoo tshaj plaws rau cov pwm kho qhov muag uas xav tau siab heev.
Txhim kho cov txheej txheem annealing: Hloov qhov kub ntawm qhov nkhaus raws li qhov zoo ntawm cov khoom. Piv txwv li, qhov kub ntawm cov txheej txheem annealing rau zirconia pwm yuav tsum tau khaws cia ntawm 1100 thiab 1200℃(qis dua qhov kub ntawm sintering ntawm 300-400 degree). Cov cua kub yuav tsum yog 5-10℃/ h (rau nyias-walled qhov chaw, nws yuav tsum tau qis dua 3℃/ h), thiab lub sij hawm rwb thaiv tsev yuav tsum yog 2-3 teev.
Kev laus los ntawm kev co: Nws yog qhov zoo rau cov pwm loj lossis cov xwm txheej uas cua sov tsis tuaj yeem vim nws siv cov khoom siv vibration (15-100Hz) los txo cov khoom siv sab hauv. Piv txwv li, ib lub tuam txhab uas ua rau lub tsheb pwm txiav pwm deformation los ntawm 60% tom qab siv kev co aging kho.
Kev kho mob nrog kev txhaj tshuaj peening: Kev cuam tshuam rau saum npoo nrog siab - cov khoom siv hlau nrawm tsim cov txheej txheem kev ntxhov siab (qhov tob 0.1-0.5mm) uas ua rau nws kav ntev dua. Zoo rau cov pwm uas muaj kev ntxhov siab nyob rau hauv lawv qhov chaw, suav nrog tuag- casting pwm thiab forging pwm.
3. Cov txheej txheem sib xyaw: Txhim kho kev ua tau zoo los ntawm kev ua haujlwm ua ke nrog cov phiaj xwm sib txawv
Kev kho cua sov thiab kev kho tshuab: Ua ntej, siv annealing kom tshem tawm tag nrho cov kev ntxhov siab, thiab tom qab ntawd siv kev txhaj tshuaj peening los ua kom lub ntsej muag muaj zog. Piv txwv li, ib lub tuam txhab aviation pwm siv cov txheej txheem ntawm "annealing (650℃rwb thaiv tsev rau 2 teev) + tua blasting (Al2O3 hais, siab 0.3MPa)," uas ua rau cov pwm ciaj sia peb zaug ntev dua.
Intelligent Annealing Technology: Ib qho AI system kho qhov kub thiab txias ntawm lub sijhawm tiag tiag kom kov yeej qhov teeb meem ntawm qhov tsis sib xws ntawm cov txheej txheem pwm nyuaj. Piv txwv li, ib pab neeg tshawb fawb tau tsim ib txoj kev ntse annealing uas tuaj yeem nce qhov kev ntxhov siab ntawm qhov tsis xwm yeem los ntawm 70% mus rau 92%.