Vim li cas cov ntawv tshaj tawm - ua cov hlau 3D luam ntawv hauv kev lag luam kho mob xav tau kev kho cua sov?

1. Tshem tawm cov kev ntxhov siab uas seem: tiv thaiv kev cog hniav tsis ua hauj lwm thiab distortion
Hlau 3D luam ntawv, zoo li laser xaiv melting (SLM), ua pwm los ntawm melting hlau hmoov txheej los ntawm txheej. Txawm li cas los xij, cua sov thiab txias cov khoom sai heev yuav ua rau muaj kev ntxhov siab hauv nws. Yog tias qhov kev ntxhov siab no tsis tso tawm sai sai, nws tuaj yeem ua rau muaj teeb meem hauv qab no:
Warping thiab cracking: Yog hais tias cov residual kev nyuaj siab yog siab tshaj cov khoom yield zog, lub implants yuav hloov cov duab mus tas li los yog txawm tawg nyob rau hauv thawj ob peb lub lis piam ntawm kev siv nyob rau hauv lub cev. Piv txwv li, yog tias muaj kev ntxhov siab ntau ntawm titanium alloy acetabular khob, nws tuaj yeem txav tau thaum tus neeg mob rov qab los ntawm kev phais vim tias qhov kev ntxhov siab tso tawm, uas tuaj yeem txhais tau tias tus neeg mob xav tau kev phais thib ob.
Txo qhov tseeb qhov tseeb: Kev ntxhov siab -vim deformation tuaj yeem cuam tshuam qhov sib xws ntawm cov khoom cog thiab tib neeg cov ntaub so ntswg. Rau kev cog hniav, piv txwv li, cov xov precision yuav tsum tau tswj kom nyob rau hauv ib lub micrometer, thiab cov kev ntxhov siab seem yuav ua rau cov xov hloov pauv, uas tuaj yeem cuam tshuam qhov kev ruaj ntseg ntawm cov pob txha alveolar.
Shortened fatigue lub neej: Implants feem ntau yuav tawg nyob rau hauv kev nyuaj siab cycling. Cov kev tshawb fawb qhia tias lub voj voog qis qis ntawm lub neej ntawm 3D luam ntawv cobalt chromium alloy txhawb nqa, tsis muaj kev kho cua sov, yog txo qis los ntawm ntau dua 40% piv rau cov khoom siv sib xyaw ua ke.
Kev ntxhov siab tuaj yeem ua tau los ntawm kev kho cua sov zoo li lub tshuab nqus tsev annealing. Nyob rau hauv cov txheej txheem no, cov cog cog yog rhuab mus rau qhov kub thiab txias (feem ntau yog qis dua qhov kub ntawm recrystallization), tuav rau ib pliag, thiab maj mam txias kom cov khoom hauv cov nplej tuaj yeem rov qab tau thiab rov ua dua tshiab, uas txo cov kev ntxhov siab. Piv txwv li, lub tshuab nqus tsev annealing ntawm 650℃txo qhov kev ntxhov siab ntawm 3D luam titanium alloy orthopedic cog los ntawm ntau dua 80% thiab txhim kho lawv cov qauv kev ruaj ntseg.
2. Txhim kho microstructure: ua kom muaj zog thiab sib haum nrog cov khoom muaj sia
Kev ruaj khov sai ntawm cov hlau 3D luam ntawv tuaj yeem ua rau qhov tsis sib xws ntawm microstructure, xws li cov kab nrib pleb, theem metastable, thiab porosity. Qhov no tuaj yeem ua rau implants ua haujlwm tsis zoo tag nrho.
Deterioration ntawm txhua yam khoom: Cov qauv siv lead ua columnar tuaj yeem ua rau anisotropy, ua rau cov cog cog kom muaj zog ntau dua hauv qee qhov kev qhia dua lwm tus. Yog hais tias 3D luam tawm nickel titanium alloy vascular stent muaj cov kab nrib pleb ntxhib, piv txwv li, nws lub zog txhawb nqa radial yuav yog 30% qis dua li cov ntaub so ntswg homogeneous equiaxed siv lead ua.
Cov porosity siab: Thaum cov hmoov hmoov tsis ua tiav thaum lub sij hawm luam ntawv, lawv tsim micropores, uas ua rau cov khoom tsis tshua muaj ntom. Yog tias qhov porosity ntau dua 1%, qhov kev cog qoob loo ntawm lub zog qaug zog tuaj yeem poob ntau dua 50%, thiab kev phom sij ntawm corrosion yuav nce mus.
Kev pheej hmoo Biocompatibility: Cov theem tsis ruaj khov, xws li martensite, tuaj yeem tso tawm cov ions lom thiab ua rau mob. Piv txwv li, yog tias muaj ntau ntawm martensite tshuav nyob rau hauv 3D luam ntawv cobalt chromium alloys, lub emission ntawm npib tsib xee ions tej zaum yuav ntau tshaj li ib txwm, uas tej zaum yuav ua rau ua xua nyob rau hauv cov ntaub so ntswg nyob ze.
Los ntawm kev tswj qhov kub thiab txias, kev kho cua sov ua kom zoo rau microstructure:
Annealing: ua rau columnar crystals tig mus rau hauv equiaxed crystals thiab tau tshem ntawm metastable theem. Piv txwv li, tom qab annealing ntawm 750 degree, lub grain loj ntawm 3D - luam titanium alloy yog refined tsawg tshaj li 10 μm, thiab cov anisotropy yog npaum li cas txo.
Kub isostatic nias (HIP): Tshem tawm ntawm qhov pores ntawm qhov kub thiab txias (feem ntau 100-200MPa) kom tau txais cov khoom ntom ntom ze li 100%. Kev tshawb fawb qhia tias kev kho HIP tuaj yeem txo qhov porosity ntawm 3D luam ntawv cobalt chromium alloys los ntawm 0.8% mus rau 0.02% thiab txhim kho lub neej qaug zog los ntawm peb zaug.
Kev daws teeb meem ntxiv rau hnub nyoog: Rau cov ntaub ntawv nco zoo li npib tsib xee titanium alloys, cov khoom siv kho mob dissolves cov theem detrimental, thaum laus kev kho mob precipitates ntxiv dag zog rau theem. Qhov no sib npaug zog nrog superelasticity. Piv txwv li, lub zog txhawb nqa radial ntawm 3D luam tawm nickel titanium alloy vascular stents tau nce 20% tom qab cov khoom siv kho mob ntawm 500℃thiab kev laus ntawm 400 degree. Daim ntawv rov qab tus nqi kuj nce mus txog 99%.
3. Ua raws li cov kev xav tau ntawm kev kho mob: ib qho kev lees paub ob npaug ntawm kev hloov kho thiab kev ua haujlwm
Kev cog hniav kho mob yuav tsum tau ua kom haum rau tus neeg mob tus qauv anatomical thaum ua tiav cov kev ua haujlwm tshwj xeeb, xws li kev sib koom ua ke ntawm pob txha thiab kev tso tshuaj. Kev kho cua sov pab nrog kev siv tshuaj kho mob raws li hauv qab no:
Kev sib xyaw ua ke ntawm kev kho cua sov nrog rau lwm txoj kev kho saum npoo zoo li sandblasting thiab acid etching tuaj yeem ua rau saum npoo ntawm cov nroj tsuag rougher thiab pab cov pob txha pob txha lo rau lawv zoo dua. Piv txwv li, tom qab annealed thiab sandblasted, nto roughness (Ra) ntawm 3D luam titanium alloy hip pob qij txha yog 3-5 μm, thiab qhov ceev ntawm cov pob txha integrate yog 40% sai dua nyob rau hauv du nto.
3D luam ntawv tuaj yeem ua cov qauv ntxeem tau nrog 30% mus rau 80% porosity thiab pore qhov ntau thiab tsawg ntawm 100 txog 1000 μm, uas zoo ib yam li cov pob txha trabeculae ua haujlwm li cas. Kev kho cua sov ua kom cov qauv nyob ruaj khov los ntawm kev tshem tawm ntawm kev ntxhov siab nyob rau hauv qhov chaw ntxeem tau. Piv txwv li, tom qab kev kho HIP, ntxeem tau titanium alloy interbody fusion li tuaj yeem tiv taus qhov siab tshaj 100 MPa, uas yog qhov yuav tsum tau siv rau kev kho mob.
Kev them nyiaj yug tshuaj: cov khoom siv cua sov tuaj yeem hloov kho cov yam ntxwv ntawm lawv qhov chaw, muab cov tshuaj pleev xim rau qhov chaw lo. Piv txwv li, ib txheej ntawm magnesium oxide ua rau saum npoo ntawm 3D - luam tawm magnesium alloy vascular stent tom qab annealing. Cov txheej no tuaj yeem tuav cov tshuaj tiv thaiv - cov tshuaj tiv thaiv kab mob los ntawm kev siv lub cev kom ua tiav cov kev tso tawm hauv zos.
4. Cov qauv kev lag luam thiab cov ntawv pov thawj yuav tsum muaj: kev kho cua sov yuav tsum tau ua
Kev cog hniav kho mob yuav tsum tau lees paub los ntawm pawg nruj xws li FDA, CE, thiab NMPA. Kev kho cua sov yog ib feem tseem ceeb ntawm cov txheej txheem ntawv pov thawj:
ISO 13485 tus qauv hais tias cov neeg cog cog cog qoob loo yuav tsum khaws cov ntaub ntawv ntxaws ntxaws ntawm tag nrho cov txheej txheem kev kho cua sov, suav nrog kev ntsuas kub, tswj huab cua, thiab cov ntaub ntawv ntsuas.
ASTM F3001 tus qauv hais tias qhov ntsuas kub rau 3D luam ntawv titanium alloy cog yuav tsum khaws cia ntawm 650 thiab 750℃kom cov nplej tsis txhob ntxhib dhau.
YY / T 0640 tus qauv: Tom qab kev kho HIP, cobalt chromium alloy implants yuav tsum muaj qhov porosity tsis pub tshaj 0.1% thiab tsis tas yuav pore chains.