Daim ntawv thov ntawm beam shaping technology hauv hlau laser additive manufacturing

Kev siv tshuab laser additive manufacturing (AM), nrog nws cov txiaj ntsig ntawm kev tsim khoom raug siab, muaj zog yooj ywm, thiab qib siab ntawm kev ua haujlwm tsis siv neeg, yog siv dav hauv kev tsim cov khoom tseem ceeb hauv cov teb xws li tsheb, kev kho mob, aerospace, thiab lwm yam (xws li rocket roj nozzles, satellite antenna brackets, tib neeg cog, thiab lwm yam). Cov thev naus laus zis no tuaj yeem txhim kho kev ua haujlwm ua ke ntawm cov khoom luam tawm los ntawm kev tsim khoom sib xyaw ntawm cov qauv khoom siv thiab kev ua tau zoo. Tam sim no, laser additive manufacturing technology feem ntau siv lub teeb Gaussian uas muaj qhov chaw siab thiab qhov faib hluav taws xob qis. Txawm li cas los xij, nws feem ntau tsim cov thermal gradients siab hauv cov yaj, ua rau muaj cov qhov hws thiab cov noob loj tom qab. Beam shaping technology yog ib txoj hauv kev tshiab los daws qhov teeb meem no, uas txhim kho kev ua haujlwm luam ntawv thiab zoo los ntawm kev kho qhov faib hluav taws xob laser.

Piv nrog rau kev rho tawm ib txwm thiab kev tsim khoom sib npaug, cov thev naus laus zis tsim khoom siv hlau ntxiv muaj qhov zoo xws li lub sijhawm luv luv ntawm kev tsim khoom, kev ua tiav siab, kev siv cov khoom siv siab, thiab kev ua tau zoo tag nrho ntawm cov khoom. Yog li ntawd, cov thev naus laus zis tsim khoom siv hlau ntxiv tau siv dav hauv kev lag luam xws li aerospace, riam phom thiab khoom siv, nuclear fais fab, biopharmaceuticals, thiab tsheb. Raws li lub hauv paus ntsiab lus ntawm kev sib cais, kev tsim khoom siv hlau ntxiv siv lub zog (xws li laser, arc, lossis electron beam) los yaj cov hmoov lossis hlau, thiab tom qab ntawd sib sau ua ke lawv txheej los ntawm txheej los tsim cov khoom siv lub hom phiaj. Cov thev naus laus zis no muaj qhov zoo tseem ceeb hauv kev tsim cov khoom me me, cov qauv nyuaj, lossis cov khoom siv tus kheej. Cov ntaub ntawv uas tsis tuaj yeem lossis nyuaj rau ua tiav siv cov txheej txheem ib txwm muaj kuj tsim nyog rau kev npaj siv cov txheej txheem tsim khoom ntxiv. Vim yog cov txiaj ntsig saum toj no, cov thev naus laus zis tsim khoom ntxiv tau nyiam cov kws tshawb fawb hauv tsev thiab thoob ntiaj teb. Hauv ob peb xyoos dhau los, cov thev naus laus zis tsim khoom ntxiv tau ua tiav sai. Vim yog kev siv tshuab thiab kev ywj pheej ntawm cov khoom siv laser tsim khoom ntxiv, nrog rau cov txiaj ntsig dav dav ntawm lub zog laser siab thiab kev ua tiav siab, cov thev naus laus zis tsim khoom ntxiv laser tau tsim kho sai tshaj plaws ntawm peb cov thev naus laus zis tsim khoom siv hlau ntxiv uas tau hais los saum toj no.

Cov txheej txheem tsim cov hlau ntxiv laser tuaj yeem muab faib ua LPBF thiab DED. Daim duab 1 qhia txog daim duab qhia txog cov txheej txheem LPBF thiab DED. Cov txheej txheem LPBF, tseem hu ua Selective Laser Melting (SLM), tuaj yeem tsim cov khoom siv hlau nyuaj los ntawm kev luam theej cov teeb laser muaj zog siab raws txoj kev ruaj khov ntawm qhov chaw ntawm lub txaj hmoov. Tom qab ntawd, cov hmoov yaj thiab khov ua txheej los ntawm txheej. Cov txheej txheem DED feem ntau suav nrog ob txoj kev luam ntawv: laser melting deposition thiab laser wire feeding additive manufacturing. Ob qho tib si ntawm cov thev naus laus zis no tuaj yeem tsim thiab kho cov khoom siv hlau ncaj qha los ntawm kev pub cov hmoov hlau lossis hlau sib dhos. Piv rau LPBF, DED muaj kev tsim khoom ntau dua thiab thaj chaw tsim khoom loj dua. Tsis tas li ntawd, txoj kev no kuj tseem tuaj yeem npaj cov khoom sib xyaw thiab cov khoom siv ua haujlwm tau yooj yim. Txawm li cas los xij, qhov zoo ntawm qhov chaw luam tawm los ntawm DED yeej ib txwm tsis zoo, thiab kev ua tiav tom qab ntawd yog qhov xav tau los txhim kho qhov tseeb ntawm cov khoom siv.

Hauv cov txheej txheem tsim khoom siv laser tam sim no, lub teeb Gaussian uas tsom mus rau feem ntau yog qhov chaw muaj zog. Txawm li cas los xij, vim nws qhov kev faib hluav taws xob tshwj xeeb (qhov chaw siab, ntug qis), nws yuav ua rau muaj kev hloov pauv kub thiab tsis ruaj khov ntawm lub pas dej yaj. Ua rau cov khoom luam tawm tsis zoo. Tsis tas li ntawd, yog tias qhov kub ntawm lub pas dej yaj siab dhau, nws yuav ua rau cov hlau yaj qis qis ua pa, ua rau qhov tsis ruaj khov ntawm cov txheej txheem LBPF hnyav dua. Yog li ntawd, nrog rau kev nce hauv porosity, cov khoom siv kho tshuab thiab lub neej qaug zog ntawm cov khoom luam tawm raug txo qis heev. Kev faib hluav taws xob tsis sib xws ntawm Gaussian beams kuj ua rau kev siv hluav taws xob laser qis thiab pov tseg hluav taws xob ntau dhau. Yuav kom ua tiav qhov zoo ntawm kev luam ntawv, cov kws tshawb fawb tau pib tshawb nrhiav kev them nyiaj rau qhov tsis zoo ntawm Gaussian beams los ntawm kev hloov kho cov txheej txheem xws li lub zog laser, kev ceev scanning, tuab txheej hmoov, thiab txoj kev scanning, txhawm rau tswj tau qhov ua tau ntawm kev nkag mus rau lub zog. Vim yog lub qhov rais ua haujlwm nqaim heev ntawm txoj kev no, cov kev txwv lub cev ruaj khov txwv tsis pub muaj kev ua kom zoo dua. Piv txwv li, kev nce lub zog laser thiab kev ceev ntawm kev luam theej duab tuaj yeem ua tiav kev tsim khoom zoo, tab sis feem ntau los ntawm tus nqi ntawm kev txo qis qhov zoo ntawm kev luam ntawv. Nyob rau hauv xyoo tas los no, kev hloov pauv lub zog laser faib los ntawm cov tswv yim beam shaping tuaj yeem txhim kho kev tsim khoom zoo thiab kev luam ntawv zoo, uas yuav dhau los ua kev coj ua yav tom ntej ntawm kev tsim khoom siv laser additive manufacturing technology. Beam shaping technology feem ntau yog hais txog kev kho qhov kev faib tawm ntawm lub wavefront ntawm lub beam input kom tau txais qhov kev faib tawm ntawm lub zog thiab cov yam ntxwv ntawm kev nthuav dav. Daim ntawv thov ntawm beam shaping technology hauv cov khoom siv hlau additive manufacturing technology tau qhia hauv Daim Duab 2.

Kev siv tshuab beam shaping hauv laser additive manufacturing

Qhov tsis zoo ntawm kev luam ntawv Gaussian beam ib txwm muaj

Hauv kev siv tshuab laser hlau ntxiv rau kev tsim khoom, lub zog faib ntawm lub teeb laser muaj qhov cuam tshuam loj rau qhov zoo ntawm cov khoom luam tawm. Txawm hais tias Gaussian beams tau siv dav hauv cov khoom siv laser hlau ntxiv rau kev tsim khoom, lawv raug kev txom nyem los ntawm qhov tsis zoo xws li kev luam ntawv tsis ruaj khov, kev siv hluav taws xob tsawg, thiab cov qhov rai nqaim hauv cov txheej txheem tsim khoom ntxiv. Ntawm lawv, cov txheej txheem yaj ntawm cov hmoov thiab lub zog ntawm lub pas dej molten thaum lub sijhawm ua cov txheej txheem laser ntxiv rau hlau muaj feem cuam tshuam nrog qhov tuab ntawm cov txheej hmoov. Vim muaj cov hmoov splashing thiab thaj chaw erosion, qhov tuab tiag tiag ntawm cov txheej hmoov yog siab dua li qhov kev cia siab theoretical. Qhov thib ob, lub kem pa ua rau lub dav hlau rov qab tseem ceeb splashes. Cov pa hlau sib tsoo nrog phab ntsa tom qab los tsim splashes, uas tau txau raws phab ntsa pem hauv ntej perpendicular rau thaj chaw concave ntawm lub pas dej molten (raws li pom hauv Daim Duab 3). Vim muaj kev sib cuam tshuam nyuaj ntawm lub teeb laser thiab splashes, cov splashes ejected tuaj yeem cuam tshuam loj rau qhov zoo ntawm kev luam ntawv ntawm cov txheej hmoov tom ntej. Tsis tas li ntawd, kev tsim cov qhov tseem ceeb hauv lub pas dej yaj kuj tseem cuam tshuam loj rau qhov zoo ntawm cov khoom luam tawm. Cov qhov sab hauv ntawm daim ntawv luam tawm feem ntau yog tshwm sim los ntawm cov qhov xauv tsis ruaj khov.

Lub mechanism ntawm kev tsim cov defects hauv beam shaping technology

Cov thev naus laus zis ua kom zoo nkauj ntawm cov nqaj tuaj yeem ua tiav kev txhim kho kev ua tau zoo hauv ntau qhov ntev tib lub sijhawm, uas txawv ntawm Gaussian beams uas txhim kho kev ua tau zoo hauv ib qho ntev ntawm tus nqi ntawm kev txi lwm qhov ntev. Cov thev naus laus zis ua kom zoo nkauj ntawm cov nqaj tuaj yeem kho qhov kub thiab txias faib thiab cov yam ntxwv ntws ntawm cov pas dej yaj. Los ntawm kev tswj hwm kev faib tawm ntawm lub zog laser, lub pas dej yaj ruaj khov nrog qhov kub me me tau txais. Kev faib tawm lub zog laser tsim nyog yog qhov zoo rau kev tswj hwm porosity thiab sputtering defects, thiab txhim kho qhov zoo ntawm kev luam ntawv laser ntawm cov khoom hlau. Nws tuaj yeem ua tiav ntau yam kev txhim kho hauv kev ua haujlwm ntau lawm thiab kev siv hmoov. Tib lub sijhawm, cov thev naus laus zis ua kom zoo nkauj ntawm cov nqaj muab rau peb ntau txoj hauv kev ua tiav, tso cai rau kev ywj pheej ntawm kev tsim cov txheej txheem, uas yog kev nce qib hauv kev siv tshuab laser additive manufacturing.