01
Taw qhia
Laser vuam tshuab, nrog nws qhov zoo ntawm lub zog muaj zog, siab precision, thiab tsawg distortion, tau dhau los ua cov txheej txheem tseem ceeb hauv kev tsim khoom niaj hnub no. Txawm li cas los xij, nws cov yam ntxwv melting sai thiab solidification ntsib teeb meem thaum ua cov ntaub ntawv muaj txiaj ntsig zoo (xws li tooj liab thiab txhuas), suav nrog kev nqus tsis ruaj khov, tsis muaj porosity, thiab thermal tawg. Qhov no yog qhov tshwj xeeb tshaj yog thaum vuam cov ntaub ntawv sib txawv, qhov uas tsim cov nkig intermetallic tebchaw ua rau kev sib koom ua haujlwm tsis muaj zog. Cov kev tsis sib haum xeeb no txwv cov ntawv thov ntxiv hauv siab -kawg teb xws li cov roj teeb fais fab thiab aerospace. Nyob rau hauv xyoo tas los no, ultrasonic vibration technology tau nce nkag mus rau hauv lub tshav pob ntawm cov khoom siv los txhim kho cov txheej txheem ib txwm muaj thiab ua tiav kev tsim khoom tsis tau muaj dua. Tshaj li nws cov ntawv thov uas twb muaj lawm hauv kev tu, sonochemistry, hlau kho, thiab atomisation, ultrasound yog maj mam dhau los ua ib qho tseem ceeb hauv kev tsim cov txheej txheem, suav nrog precision machining, advanced vuam, laser ua, thiab additive manufacturing. Txog qhov kawg no, kom kov yeej qee qhov kev txwv hauv laser vuam, ib qho kev daws teeb meem tshiab -ultrasonic vibration- pab laser vuam (UVA-LW)- tau tshwm sim (Daim duab 1). Cov thev naus laus zis no muaj tswv yim nthuav qhia siab - zaus ultrasonic vibration rau hauv cov txheej txheem laser vuam, aiming siv lub cim acoustic ntws, cavitation, thiab kev ntxhov siab ntawm ultrasound rau lub cev cuam tshuam rau hauv cov ntws, roj tus cwj pwm, thiab solidification txheej txheem ntawm lub pas dej ua ke molten. Los ntawm qhov no 'acousto-optic synergy', UVA{16}}LW thev naus laus zis tuaj yeem ua kom lub pas dej molten zoo, txhawb kev degassing, refine nplej, thiab inhibit qhov tsim ntawm nkig theem, yog li txhim kho vuam zoo thiab kev ua tau zoo thiab qhib txoj hauv kev tshiab cog lus rau kev daws cov teeb meem ntawm cov khoom siv laser.
Daim duab 1. Schematic diagram: (a) UVA-LW kev sim teeb tsa; (b) morphology ntawm lub pas dej molten thaum lub sij hawm UVA-LW txheej txheem; (c) cov yam ntxwv ntawm lub pas dej molten ntws thaum lub sij hawm UVA-LW txheej txheem [1].
Lub hauv paus ntsiab lus: Synergistic Effect of Sound and Light
Lub ntsiab lus ntawm ultrasonic kev co- pab laser vuam lies nyob rau hauv lub optimization tiav los ntawm lub acoustic zog teb nyob rau hauv tag nrho cov txheej txheem ntawm laser vuam, los ntawm lub cev tus cwj pwm ntawm cov kua molten pas dej ua ke, los ntawm lub koom haum evolution thaum lub sij hawm solidification, mus rau cov kev cai ntawm kev nyuaj siab nyob rau hauv cov khoom ntawm lub xeev tom qab txias. Ua ntej, ntawm cov kua theem, siab - zaus ultrasonic tsis ua rau muaj zog acoustic streaming thiab cavitation cuam tshuam nyob rau hauv lub molten pas dej ua ke, ua raws li ib tug "microscopic stirrer" thiab "ntau purifier" rau cov hlau molten. Cov kev taw qhia macroscopic ntws tsim los ntawm acoustic streaming ua zoo li cov khoom siv sab hauv, ua rau muaj kev ntxhov siab rau lub pas dej ua ke, yog li tswj cov khoom sib faib ntawm cov ntsiab lus thiab qhov kub thiab txias. Qhov no yog qhov tseem ceeb tshwj xeeb tshaj yog thaum vuam cov ntaub ntawv sib txawv, vim nws cuam tshuam cov nkig intermetallic tebchaw uas zoo li tsim cov khaubncaws sab nraud povtseg ntawm qhov sib txuas, faib lawv kom zoo thiab sib npaug, yog li txhim kho kev sib koom ua ke. Nyob rau tib lub sijhawm, cov nyhuv cavitation hnyav dua, los ntawm kev tawg sai sai ntawm suav tsis txheeb microbubbles, tso tawm lub zog poob siab thiab siab - microjets ceev. Qhov no tsis tsuas yog tshem tawm cov yeeb yaj kiab oxide ntawm lub pas dej molten los txhim kho cov dej ntub dej, tab sis kuj tshem tawm cov pa phem xws li hydrogen thiab nitrogen los ntawm lub pas dej, yuam kom lawv khiav tawm sai thiab hauv paus tiv thaiv kev tsim cov porosity tsis xws luag. Tom qab ntawd, thaum lub sij hawm solidification theem, lub sij hawm siab siab - lub zog poob siab tsis tau tsim los ntawm cavitation nyhuv los ua ib tug haib cuab tam rau kev tswj lub solidification qauv. Raws li lub pas dej molten txias thiab dendrites loj tuaj, cov kev poob siab no ua rau lawv tawg thiab tawg. Lub caj npab fragmented dendrite, nqa thoob plaws hauv lub pas dej los ntawm acoustic streaming, ua raws li ntau yam tshiab uas tsis yog - qhov chaw nucleation tshwm sim, ua tiav "fragmented proliferation" ntawm nuclei. Cov txheej txheem no tau hloov pauv cov qauv kev ua kom muaj zog ib txwm muaj, txo qis kev loj hlob ntawm coarse columnar crystals thiab ua rau muaj kev ua tau zoo ntawm - weld qauv tsim los ntawm ntau cov nplua nuj, zoo li equiaxed crystals, zoo heev txhim kho lub weld lub zog, ductility thiab tiv thaiv thermal cracking. Thaum kawg, hauv cov khoom txias txias- xeev theem, ultrasonic kev co tseem ua lub luag haujlwm tseem ceeb hauv acoustic softening thiab txo kev ntxhov siab. Cov nyhuv acoustic softening ib ntus softens cov weld thiab tshav kub- cov ntaub ntawv cuam tshuam rau hauv lawv qhov siab -cov yas yas kub, ua rau lawv muaj peev xwm ua kom haum thiab so kom txaus siab los ntawm kev ua kom txias los ntawm cov yas deformation microscopic. Tsis tas li ntawd, kev txhawb siab siab - zaus tshuab kev co muab lub zog ntxiv rau kev tsiv teb tsaws ntawm atoms thiab dislocations, txhawb kev rov faib thiab so ntawm kev ntxhov siab sab hauv. Yog li ntawd, los ntawm purification thiab homogenisation ntawm cov kua, mus rau grain refinement thaum lub sij hawm solidification, thiab kev nyuaj siab nyem nyob rau hauv cov khoom ntawm lub xeev, ultrasonic kev co, los ntawm no series ntawm interrelated lub cev los, tsim ib tug npaum synergistic ua hauj lwm nrog lub laser tshav kub qhov chaw, systematically hais txog cov tseem ceeb cov kev cov nyom ntawm tsoos laser vuam . ...
Daim duab 2. Cov nyhuv ntawm ultrasound ntawm cov kua dej ntws hauv lub pas dej molten: (a) tsis muaj ultrasound; (b) nrog ultrasound [1].
03
Application Advantages: Kev txhim kho tseem ceeb hauv kev ua tau zoo thiab kev ua tau zoo
Lub hauv paus ntsiab lus tseem ceeb ntawm photoacoustic synergy thaum kawg txhais ua ib qho tseem ceeb hauv kev vuam zoo thiab kev sib koom ua haujlwm. Piv nrog rau cov tsoos laser vuam, ultrasonic kev co- pab laser vuam qhia peb qhov zoo hauv kev hais txog kev lag luam mob cov ntsiab lus:
3.1 Txo cov vuam tsis xws luag (Porosity, tawg)
Porosity thiab kab nrib pleb yog ob qhov "killers" loj cuam tshuam rau kev ntseeg tau ntawm vuam, thiab ultrasonic kev co muaj zog inhibitory nyhuv ntawm cov no.
(1) Inhibition ntawm porosity: Nyob rau hauv ib txwm laser welding, tshwj xeeb tshaj yog sib sib zog nqus welding, porosity yog yooj yim tsim vim lub instability ntawm lub keyhole thiab entrainment ntawm hlau vapor. Kev taw qhia ntawm ultrasound muab lub zog degassing quab yuam rau lub pas dej molten los ntawm cavitation thiab acoustic streaming teebmeem. Ntawm ib sab tes, kev poob siab tsis tau tsim los ntawm lub cev qhuav dej ntawm cov npuas cavitation tuaj yeem ua rau tawg me me hydrogen thiab nitrogen npuas nyob rau hauv lub pas dej molten los yog yuam kom lawv coalesce thiab nce sai. Ntawm qhov tod tes, qhov sib txuas txuas ntxiv ntawm acoustic streaming muaj txoj hauv kev thiab buoyancy rau npuas khiav. This significantly improves weld density, reducing porosity by an order of magnitude or more, which is crucial for joint sealing and fatigue life.
(2) Inhibition ntawm tawg tsim: Vuam kab nrib pleb tuaj yeem muab faib ua cov tawg kub thiab cov kab nrib pleb txias. Rau cov kab tawg kub, ultrasonic kev co hauv paus txhim kho cov qauv kev sib zog los ntawm kev rhuav tshem cov kab nrib pleb thiab ua cov hmoov nplej zoo, txo qis kev sib cais ntawm qis - melting - taw tes eutectics ntawm cov ciam teb, yog li txhim kho cov khoom tiv thaiv kom tawg hauv siab - qhov kub thiab txias. Rau cov kab nrib pleb txias, cov nyhuv ultrasonic softening thiab kev ntxhov siab tso tawm kom txo qis kev ntxhov siab tom qab vuam, tiv thaiv kev ntxhov siab, yog li zoo inhibiting txias tawg los ntawm hydrogen ncua kev tawg lossis kev ntxhov siab. Cov nyhuv no tshwj xeeb tshaj yog thaum vuam siab - lub zog steel thiab siab - cov ntaub ntawv hardness.
3.2 Txhim kho kev ua haujlwm ntawm cov khoom sib txawv ntawm cov pob qij txha
Qhov kev sib tw loj tshaj plaws hauv kev sib txawv ntawm cov hlau sib txawv yog nyob rau hauv qhov sib txawv loj hauv lub cev (xws li cov ntsiab lus melting thiab thermal conductivity) thiab nyiam tsim cov tuab thiab nkig intermetallic compounds (IMCs) ntawm qhov sib txuas, uas ua rau muaj kev sib koom ua ke loj heev. Ultrasonic vibration muab ib qho kev daws teeb meem rau qhov no:
(1) Kev Tiv Thaiv thiab kev ua kom zoo ntawm IMC txheej: Lub zog acoustic ntws ntawm ultrasonics ua raws li kev sib xyaw ua ke, rhuav tshem cov txheej txheem IMC tshiab, tiv thaiv nws txoj kev loj hlob tsis tu ncua, thiab nkag mus rau nws cov khoom tawg mus rau hauv lub pas dej ua ke, ua rau lawv muab faib rau hauv cov weld raws li zoo, dispersed hais. Nyob rau hauv txoj kev no, lub nkig theem tsis yog ib tug tsis muaj zog nruam interface tab sis yog surrounded los ntawm ib tug muaj zog thiab tawv matrix, zoo heev txhim kho lub plasticity thiab toughness ntawm kev sib koom tes. Piv txwv li, hauv txhuas / hlau thiab txhuas / tooj liab vuam, lub thickness ntawm IMC txheej tuaj yeem tswj tau zoo hauv qab tus nqi tseem ceeb ntawm ob peb microns lossis tsawg dua.
3.3 Optimization ntawm weld tsim thiab mechanical zog
Ntxiv nrog rau kev daws teeb meem tsis xws luag, ultrasonic kev co tuaj yeem ua tiav kev txhim kho qhov zoo ntawm kev tsim vuam.
(1) Kev txhim kho ntawm kev tsim cov vuam: Ultrasonic kev co txo qhov pom tseeb viscosity ntawm cov hlau molten thiab ua rau nws cov fluidity. Qhov no ua rau nws yooj yim dua rau cov kua hlau kom sib kis thiab sau, ua rau lub ntsej muag smoother thiab zoo dua qub, txo qhov kev tsim tsis xws li undercutting thiab tsis muaj kev nkag mus. Nyob rau tib lub sijhawm, kev txhim kho wettability ua rau kev hloov pauv ntawm cov vuam thiab cov khoom siv hauv paus ntau dua, txo cov ntsiab lus ntawm kev ntxhov siab.
(2) Kev txhim kho zoo ntawm cov khoom siv kho tshuab: Qhov no yog qhov kawg ntawm tag nrho cov txiaj ntsig saum toj no. Raws li kev tshem tawm cov porosity thiab microcracks, nrog rau kev ua kom zoo ntawm cov nplej tseem ceeb (Daim duab 3), lub zog thiab plasticity ntawm cov vuam tuaj yeem txhim kho ib txhij, rhuav tshem cov pa luam yeeb - tawm ntawm lub zog thiab plasticity hauv cov khoom siv niaj hnub. Cov qauv zoo equiaxed nplej ua rau txoj kev tawg pleb tortuous, zoo heev txhim kho cov pob txha toughness thiab qaug zog tiv thaiv ntawm kev sib koom tes.
04
Cov ntsiab lus
Raws li ib txoj hauv kev ua kom muaj zog sib xyaw ua ke, UVA-LW tsis yog tsuas yog ua kom zoo dua thiab ua kom zoo dua cov txheej txheem laser vuam ib txwm tab sis tseem hais txog ntau qhov ntev - cov teeb meem tseem ceeb. Los ntawm kev sib txuas ua ke ntawm qhov siab - zaus acoustic zog teb rau hauv lub pas dej laser molten, cov thev naus laus zis no ua tiav kev cuam tshuam lub cev sib sib zog nqus los ntawm 'photoacoustic synergy', txhim kho tag nrho cov saw ntawm kev ua tau zoo los ntawm cov kua purification thiab solidification microstructure tswj kom ruaj khov- xeev kev ntxhov siab.
Nrog rau qhov yuav tsum tau muaj zog ntxiv rau kev sib txuas zoo hauv thaj chaw xws li lub zog tshiab tsheb (tshwj xeeb tshaj yog tooj liab-aluminium kev sib txuas hauv cov roj teeb hluav taws xob), aerospace (lub teeb yuag siab- lub zog alloys thiab cov khoom sib txawv ntawm cov khoom sib txawv), thiab siab -kawg precision manufacturing, ultrasonic vibration- kev pab cuam muaj peev xwm lasertes. Kev tshawb fawb yav tom ntej yuav tsom mus rau 1) kev ua kom zoo dua qub thiab sib txuam ntawm ultrasonic thiab laser tsis ua kom tiav 'customized' vuam rau cov ntaub ntawv tshwj xeeb thiab kev siv; 2) kev koom ua ke nrog cov thev naus laus zis no nrog kev saib xyuas online thiab kev tswj xyuas ntse kom qhib tau kaw- lub voj voog tawm tswv yim thiab tiag- lub sijhawm lav zoo thaum lub sijhawm vuam; 3) Tshawb nrhiav nws cov ntawv thov ntxiv hauv kev txiav- ntug teb xws li kev tsim khoom ntxiv los tswj cov kev ntxhov siab thiab cov khoom siv microstructural thaum lub sijhawm luam ntawv. Nws yog qhov pom tau tias ultrasonic vibration- pab laser vuam tshuab yuav tsis tsuas yog 'cov teeb meem daws teeb meem' tab sis yuav dhau los ua 'kev ua tau zoo' tsav kev txhim kho ntawm kev tsim cov thev naus laus zis, muab txoj hauv kev ua tau zoo rau kev ua haujlwm siab dua thiab cov khoom siv txhim khu kev qha.
