Dab tsi ua rau Hlau 3D Printing txawv
Laser printing hauv hlautsim cov txheej txheej los ntawm txheej. Lub siab -lub zog laser xaiv melts hlau hmoov, tsim cov thermal gradients thaum txhua txheej melts thiab solidifies sai. Cov kev rov ua dua no ua rau muaj kev ntxhov siab tseem ceeb thiab tsis yog -cov qauv microstructures.
Raws li - ua cov hlau 3D luam tawm qhov sib txawv ntawm ib txwm muaj forged los yog cam khwb cia sib npaug. Lawv feem ntau pom muaj zog tensile ntau dua tab sis qis dua ductility, anisotropic zog, thiab kev ntxhov siab sab hauv uas tuaj yeem ncav cuag lub zog ntawm cov khoom. Qhov no ua rau muaj qhov sib txawv ntawm kev ua haujlwm uas cov ntawv kho mob - uas xav tau kev qaug zog siab thiab ntev - lub sijhawm ruaj khov nyob rau hauv cyclic loading - tsis tuaj yeem zam.
Ib lub chaw tsim tshuaj orthopedic pom tias raws li -tsim SLM Ti-6Al-4V pom 15-20% lub neej qaug zog qis dua li cua sov- kho qhov sib npaug. Hauv kev cog qoob loo, qhov sib txawv no tuaj yeem txiav txim siab qhov kev vam meej mus ntev lossis tsis ua haujlwm.
Peb qhov teeb meem tseem ceeb uas kev kho cua sov daws tau
Teeb meem 1 - Kev ntxhov siab seem: cua kub ceev thiab cua txias ua kom muaj zog tensile rau saum npoo thiab compressive stresses sab hauv. Cov no tuaj yeem ua rau muaj kev cuam tshuam, tawg, lossis ua tsis tiav ntxov thaum lub sijhawm thauj khoom.
Teeb meem 2 - Microstructural instability: Columnar grains, martensitic theem (hauv titanium), thiab tsis muaj homogenization ua rau anisotropic cwj pwm thiab txo toughness.
Teeb meem 3 - Cov cuab yeej cuab tam tsis txaus: Raws li - cov khoom tsim feem ntau tsis muaj qhov zoo sib npaug ntawm lub zog, ductility, thiab qaug zog tiv thaiv uas yuav tsum tau muaj rau kev cog qoob loo.
Cov ntaub ntawv rooj: Raws li -ua vs Kub-Tho-6Al-4V SLM
|
Khoom |
Raws li -Ua |
Stress Relieved / HIP |
Kev txhim kho |
|
UTS (MPa) |
1100–1300 |
950–1100 |
Ntau qhov sib npaug |
|
Yield zog (MPa) |
1000–1200 |
850–1000 |
Zoo sib xws |
|
Elongation (%) |
4–8 |
10–18 |
Tseem ceeb dua |
|
Fatigue Limit (MPa) |
qis |
20-50% siab dua |
Qhov tseem ceeb rau implants |
Hlau 3D luam ntawvresidual stress nyem thiab optimized microstructure yog qhov tseem ceeb rau kev ua haujlwm.
Hom kev kho cua sov siv rau kev kho mob hlau 3D luam tawm qhov chaw
Kev ntxhov siab nyem annealing: Qhov ntsuas kub qis tshaj plaws los txo cov kev ntxhov siab uas tsis muaj kev hloov pauv loj.
Kev kho thiab kev laus (STA): Optimizes lub zog thiab ductility nyob rau hauv titanium alloys.
Kub Isostatic Pressing (HIP): Siv cov cua sov thiab siab siab los kaw qhov porosity thiab txhim kho lub neej qaug zog.
Annealing rau 316L thiab CoCr: Stabilizes microstructure thiab txo kev ntxhov siab.
EBM- cov khoom luam tawm feem ntau muaj kev ntxhov siab qis dua li SLM qhov chaw vim muaj qhov kub thiab txias, xav tau cov txheej txheem sib txawv.
Cov ntaub ntawv rooj: Kev kho cua sov
|
Kev kho mob |
Lub hom phiaj |
Yam Parameters |
Cov ntaub ntawv tseem ceeb |
|
Kev ntxhov siab |
Txo kev ntxhov siab sab hauv |
600-800 degree, 1-2 teev |
Tag nrho |
|
HIP |
Porosity kaw + kev ntxhov siab |
900-1200 degree, 100-200 MPa |
Ti, CoCr |
|
STA (Ti-6Al-4V) |
Optimize + microstructure |
Kev daws teeb meem ~ 950℃+ hnub nyoog ~ 500 degree |
Titanium |
|
Lub cev muaj zog (316L) |
Austenite stabilization |
1000-1100 degree |
Stainless hlau |
Khoom siv -los ntawm - Cov Khoom Siv Thaum Kub Kub Kho Kom Zoo
Ti-6Al-4V: Feem ntau thiab nuanced. Yuav tsum tau ceev faj tswj kom ua tiav lamellar lossis equiaxed microstructure thaum khaws cia biocompatibility.
316L Stainless Hlau: Ua kom pom tseeb ntawm kev ntxhov siab thiab tsis txhob hnov qab (chromium carbide nag lossis daus).
CoCr Alloys: Tswj kev tsim carbide rau hnav tsis kam hauv kev kho hniav / orthopedic siv.
Inconel: nag lossis daus hardening rau siab - siv zog.
Kev siv cov kev ntsuas tsis raug tuaj yeem ua rau cov qoob loo loj hlob, distortion, lossis txo qhov kev tiv thaiv corrosion.
HIP - Kev kho cua sov uas ua ob lub luag haujlwm
Kub Isostatic Pressing (HIP) ib txhij siv qhov kub thiab txias thiab isostatic gas siab. Nws kaw cov porosity sab hauv (feem ntau hauv SLM) uas lwm yam kev kho mob tsis tuaj yeem hais meej thiab ua rau muaj kev ua haujlwm qaug zog.
HIP feem ntau txhim kho lub neej qaug zog los ntawm 30–100%+ hauv SLM Ti-6Al-4V los ntawm kev tshem tawm qhov chaw pib tawg. Nws feem ntau xav tau rau kev cog qoob loo tseem ceeb, txawm hais tias kev ntxhov siab ib leeg tuaj yeem txaus rau qis dua - daim ntawv thov kev pheej hmoo. Cov tuam txhab ua lag luam sib koom ua ke HIP rau nws cov txiaj ntsig zoo hauv kev ua haujlwm siab.
Kev kho cua sov li cas cuam tshuam rau lwm tus ncej-Cov kauj ruam ua haujlwm
Ib ntus tseem ceeb. Kev kho cua sov feem ntau yog ua ua ntej kawg machining kom txo tau kev ntxhov siab thiab txo qis distortion thaum machining. Nws tuaj yeem ua rau me me hloov pauv (0.1-0.5%) uas yuav tsum tau suav rau hauv kev tsim. Deg xov thiab electropolishing feem ntau ua raws li kev kho cua sov.
Cov ntaub ntawv cov lus: Tshaj tawm -Kev xaiv ua ntu zus
|
Kev xaiv ib ntus |
Qhov zoo |
Kev txiav txim siab |
|
Thaum tshav kub kub kho → Machining |
Minimizes machining distortion |
Tus account rau shrinkage |
|
Machining → Thaum tshav kub kub kho |
Precise kawg qhov ntev |
Risk ntawm distortion ncej-machining |
|
Txhawb Kev Tshem Tawm → Thaum tshav kub kub kho |
Txheem rau feem ntau cov khoom kho mob |
Tiv thaiv kev tawg thaum lub sij hawm nyem |
Tiag -Lub Ntiaj Teb Case Scenario
Case 1: Spinal tawb nrog siab residual stress fractured nyob rau hauv cyclic loading nyob rau hauv kev sim.
Case 2: CoCr kho hniav lub moj khaum tau pom qhov dav dav thaum lub sij hawm ua kom tsis muaj menyuam vim muaj qhov tsis zoo ntawm microstructural.
Case 3: Ti-6Al-4V orthopedic phaj dhau qhov kev ntsuam xyuas zoo li qub tab sis ua tsis tiav kev qaug zog; Kev kho HIP txhim kho lub neej qaug zog los ntawm ~ 40%.
Cov xwm txheej no qhia txog qhov kev pheej hmoo ntawm kev hla kev tsim cov khoom tsim kev ntxhov siab rau kev cog qoob loo.
Cov lus nug nquag
Vim li cas cov hlau 3D luam tawm yuav tsum tau kho cua sov?
Txhawm rau txo qis kev ntxhov siab, homogenize microstructure, kaw porosity, thiab ua tiav cov khoom siv kho mob uas yuav tsum tau siv rau kev nyab xeeb kev kho mob.
Dab tsi yog qhov kev kho cua sov zoo tshaj plaws rau SLM Ti-6Al-4V kev kho mob cog?
Feem ntau ua ke ntawm kev ntxhov siab los yog HIP, ua raws li kev daws teeb meem thiab kev laus, nyob ntawm cov kev xav tau tshwj xeeb.
Puas yog HIP hloov kev ntxhov siab annealing rau hlau 3D luam ntawv?
HIP tuaj yeem ua haujlwm rau ob qho tib si tab sis kim dua; ntau qhov kev ua haujlwm siv kev ntxhov siab ua ntej thiab HIP rau qhov tseem ceeb.
Kev kho cua sov li cas txhim kho lub neej qaug zog hauv laser luam ntawv hlau qhov chaw?
Los ntawm kev txo cov kev ntxhov siab seem thiab tshem tawm cov porosity uas ua raws li qhov chaw pib tawg.
Yuav ua li cas yog tias koj hla kev kho cua sov ntawm cov hlau 3D luam ntawv cog?
Ua rau muaj kev pheej hmoo ntawm kev cuam tshuam, tawg, qaug zog ntxov ntxov, thiab kev tswj tsis tau- ua raws.
Kuv yuav paub li cas yog tias kuv cov hlau 3D luam ntawv cov khoom siv hluav taws xob kho lawv cov khoom kom raug?
Thov cov ncauj lus kom ntxaws txog lub voj voog, cov ntaub ntawv siv tau, cov ntaub ntawv rau lub tshuab hluav taws xob, thiab cov txiaj ntsig ntawm kev ntsuas tshuab ntawm cov ntawv kho mob.