Cov yam ntxwv cuam tshuam rau Nto Roughness hauv Hlau 3D Printing

Qhov saum npoo roughness ntawm hlau 3D luam tawm qhov chaw sib txawv nyob ntawm ntau yam, thiab feem ntau ntog ntawm ob peb micrometers thiab ntau kaum micrometers. Tsis zoo li cov khoom siv ib txwm siv, qhov chaw ua kom tiav yog qhov ua haujlwm ntawm cov cuab yeej geometry thiab txiav tsis, hlau additive manufacturing qhia txog ntau qhov sib txawv ntawm - txheej txheem luam ntawv nws tus kheej, cov yam ntxwv ntawm cov khoom raug luam tawm, thiab tom qab- cov txheej txheem ua tiav tom qab txhua qhov cuam tshuam los txiav txim siab qhov kawg ntawm qhov chaw. Kev nkag siab tias txhua yam ntawm cov xwm txheej no pab piav qhia vim li cas ob qhov chaw luam tawm los ntawm tib tus qauv tuaj yeem xaus nrog qhov sib txawv ntawm qhov zoo.

Laser Powder txaj Fusion (L-PBF). Qhov no yog ib qho ntawm ntau hom hlau 3D luam ntawv txheej txheem siv niaj hnub no. Nws ua haujlwm los ntawm kev siv lub siab -lub zog laser los yaj cov hmoov hlau, uas yog tom qab ntawd tsim txheej txheej los ntawm txheej rau hauv qhov kawg ntawm cov duab. Nyob rau hauv cov xwm txheej zoo, qhov roughness ntawm cov txheej txheem no tuaj yeem tswj tau nyob ib ncig ntawm Ra 10-30μm. Piv txwv li, thaum luam ntawv hlau qhov chaw nrog cov qauv yooj yim siv cov txheej txheem no, cov qib qis roughness tuaj yeem ua tiav thaum qhov ntsuas tau zoo. Qhov no yog vim hais tias lub zog laser yog haum rau cov concentrated, tso cai rau kev tswj xyuas meej ntawm cov duab thiab qhov loj ntawm lub pas dej yaj. Qhov no precision txhais tau hais tias cov hmoov fuses thiab stacks ntau densely raws li nws solidifies, uas yuav pab txo tau deg roughness rau ib co degree. Qhov nruj nruj ntawm lub laser beam kuj txhais tau hais tias thermal input mus rau ib puag ncig, unmelted hmoov yuav txo tau, txo tus nqi ntawm ib nrab sintered hmoov uas nyhav rau cling rau ntawm ntug ntawm ib tug luam feature thiab pab mus rau ib tug rougher tiav.

Electron Beam Melting (EBM). Cov txheej txheem no siv lub teeb hluav taws xob los ntsuas thiab yaj cov hmoov hlau. Cov khoom luam tawm siv cov txheej txheem no feem ntau poob nyob rau hauv qhov zoo sib xws ntawm kev ntxhib los mos, tab sis cov txiaj ntsig tuaj yeem sib txawv nyob ntawm tus yam ntxwv ntawm cov kab hluav taws xob hluav taws xob thiab cov tswv yim scanning siv. Cov kab hluav taws xob muaj lub zog siab thiab muaj kev ua kom pom tseeb zoo, ua kom siab -kev ua kom tiav thiab tsim ib feem. Hauv cov ntawv thov uas qhov kev xav tau zoo tshaj plaws yog qhov xav tau tshwj xeeb, kev nplua - kho cov txheej txheem tsis tuaj yeem ua rau roughness mus ze rau Ra 10μm lossis qis dua. Nws yog ib qho tsim nyog sau cia tias EBM feem ntau yog ua los ntawm kev tsim siab siab-chamber kub thiab nyob rau hauv lub tshuab nqus tsev, uas hloov cov hmoov txaj coj zoo li cas piv rau laser- cov txheej txheem raws li - qhov kub siab txo qhov kev ntxhov siab thaum lub sij hawm tsim, tab sis nws kuj tuaj yeem ua rau cov hmoov ntau ntxiv rau qhov sib txawv ntawm qhov sib txawv me ntsis, qee zaum BM yog qhov sib txawv ntawm qhov sib txawv. roughness tus cwj pwm dua li L-PBF nto txawm tias qhov nominal roughness qhov zoo sib xws.

Cov khoom siv hlau sib txawv. Lub melting point, viscosity, thiab lwm yam lub cev yam ntxwv ntawm cov khoom muab ncaj qha cuam tshuam rau flowability thiab hmoov- kis tus cwj pwm thaum lub sij hawm luam ntawv, uas nyob rau hauv lem influences nto roughness. Piv txwv li, aluminium alloys - uas muaj qhov qis melting point thiab zoo flowability - zoo li yuav sau qhov khoob thiab tsim cov npoo du yooj yim dua thaum luam ntawv, thiab lawv qhov roughness feem ntau tuaj yeem ncav cuag qhov ntau ntawm Ra 15-25μm. Los ntawm qhov sib txawv, qee cov hlau uas muaj cov ntsiab lus melting ntau dua thiab cov viscosity ntau dua, xws li qee qhov siab -kub superalloys, yuav tsis kis tau thiab fuse zoo li thaum lub sijhawm luam ntawv, thiab lawv qhov roughness yuav khiav me ntsis siab dua - feem ntau nyob rau hauv thaj tsam ntawm Ra 20–35μm. Qhov sib txawv no tseem ceeb hauv kev xyaum: tus tsim ib feem xaiv ntawm aluminium alloy thiab npib tsib xee-raws li superalloy rau ib daim ntawv thov tsis yog tsuas yog qhov hnyav ntawm cov khoom thiab qhov kub thiab txias, tab sis kuj tseem lees txais qhov sib txawv ntawm qhov chaw ua tiav ua ntej ib qho kev tshaj tawm - ua tiav.

Alloy muaj pes tsawg leeg. Qhov kev faib ua feem ntawm cov ntsiab lus sib txawv hauv ib qho alloy kuj cuam tshuam rau saum npoo roughness. Piv txwv li, cov alloys uas muaj ntau dua ntawm cov ntsiab lus oxidized yooj yim tuaj yeem ntsib qhov zoo ntawm degradation vim oxidation tshwm sim thaum lub sij hawm luam ntawv, uas nyob rau hauv lem nce roughness. Cov nyhuv no yog qhov tshwj xeeb tshaj yog rau cov txheej txheem hlau 3D luam ntawv uas tsis ua haujlwm nyob rau hauv qhov chaw tsis muaj zog lossis lub tshuab nqus tsev, qhov twg cov pa oxygen raug thaum lub sij hawm txhua txheej txheej melting tuaj yeem sib sau ua ke rau hauv qhov ntsuas tau ntawm qhov ua tiav ntawm qhov kev tsim uas yuav koom nrog ntau txhiab tus neeg txheej.

Kev kho cua sov. Kev kho cua sov kom tsim nyog tuaj yeem txo cov kev ntxhov siab sab hauv thiab txhim kho cov txheej txheem metallurgical ntawm ib feem, yog li txo qhov roughness ntawm qhov chaw. Tom qab kev kho cua sov, ib feem ntawm qhov saum npoo yuav ua kom pom tseeb dua, nrog rau qhov roughness txo los ntawm ob peb micrometers. Piv txwv li, annealing ib feem ntawm cov hlau luam tawm tom qab tsim yuav pab kho cov qauv ntawm cov nplej, ua rau saum npoo ntawm microstructure ntau yam. Roughness tuaj yeem txo los ntawm ib puag ncig Ra 20μm ua ntej kev kho mob mus rau ib puag ncig Ra 15μm tom qab. Thaum kev kho cua sov feem ntau yog siv los txo cov kev ntxhov siab thiab txhim kho cov khoom siv xws li ductility, nws cov nyhuv ntawm qhov roughness yog ib qho txiaj ntsig thib ob - ib qho uas cov neeg tsim khoom qee zaum saib tsis taus thaum npaj ib feem ntawm tag nrho cov ncej- ua ntu zus, txawm tias nws tuaj yeem txo qhov nqi ntawm cov tshuab ua kom tiav hauv qab.

Mechanical processing. Txo roughness loj tuaj yeem ua tiav los ntawm kev ua cov txheej txheem xws li xuab zeb thiab polishing. Sanding tshem tawm nto protrusions thiab imperfections, txhim kho zuag qhia tag nrho nto flatness. Polishing ces ntxiv refines saum npoo, nqa roughness mus rau ob peb micrometers los yog qis dua. Piv txwv li, tom qab polishing zoo, qhov roughness ntawm cov hlau 3D luam tawm tuaj yeem ncav cuag hauv qab Ra 5μm, ua tau raws li qhov xav tau ntawm cov ntawv thov nrog cov kev xav tau siab heev, xws li cov khoom siv kho qhov muag. Qhov kev ua tiav zoo li no - kev kho cua sov kom ruaj khov rau cov khoom siv, ua raws li cov xuab zeb kom tshem tawm tag nrho cov nta saum npoo, ua raws li polishing kom ua tiav qhov kawg ntawm qhov zoo - qhia txog yuav ua li cas roughness txo nyob rau hauv hlau additive manufacturing tsis tshua muaj ua tiav los ntawm ib kauj ruam. Hloov chaw, nws feem ntau muaj kev sib xyaw ua ke ntawm kev kho cua sov thiab kho tshuab, txhua qhov hais txog qhov sib txawv ntawm qhov sib txawv ntawm qhov tsis sib xws, los ntawm kev ntxhov siab ntau mus rau micron- theem smoothness.

Muab tag nrho, peb pawg ntawm yam tseem ceeb no - hom txheej txheem, cov khoom siv, thiab tshaj tawm- txheej txheem txheej txheem - cuam tshuam ntau dua li ua nws tus kheej. Ib feem luam tawm ntawm L-PBF los ntawm qis-viscosity aluminium alloy nrog zoo-cov kev ntsuas qhov zoo tuaj yeem ua tiav ib qho txiaj ntsig zoo li- ua roughness, thaum tib tus qauv luam tawm los ntawm siab -viscosity superalloy ntawm EBM yuav pib los ntawm ib qho rougher postprocess{9} txawm tias ua ntej Qhov no txhais tau hais tias ua tiav lub hom phiaj saum npoo tiav rau ib daim ntawv thov tsis yog ib qho teeb meem ntawm kev qhia ib qho kev tshaj tawm - cov kauj ruam ua tiav ntawm qhov kawg ntawm kev ua haujlwm - nws yuav tsum xav txog cov txheej txheem thiab cov khoom siv los ntawm qhov pib, txij li cov kev txiav txim siab saum toj no tau teeb tsa cov tswv yim hauv pem teb thiab qab nthab rau dab tsi ncej - kev ua tiav tuaj yeem ua tiav. Rau cov ntawv thov uas yuav tsum tau ua kom tiav cov txheej txheem nruj, kev nkag siab yuav ua li cas cov kev sib txawv no cuam tshuam rau cov engineers xaiv txoj kev sib xyaw ua ke ntawm cov txheej txheem, cov khoom siv, thiab kev ua tiav los ntawm qhov pib, es tsis txhob sim them nyiaj rau qhov tsis zoo ntawm qhov chaw pib los ntawm kev ua haujlwm ntau thiab nqi qis.