Laser ntxuav thiab pleev xim daim ntawv thov tau txais kev saib xyuas ntau nyob rau hauv xyoo tas los no, raws li cov txheej txheem tshem tawm cov xim xws li sandblasting thiab tshuaj pleev xim stripping ua rau muaj kuab paug ib puag ncig. Nws yog lub sijhawm los coj kom zoo dua cov xim ntsuab tshem tawm cov kev daws teeb meem. Los ntawm kev tswj hwm kom zoo xws li pulse dav, lub zog ua haujlwm, thiab tshem tawm cov kev ua haujlwm loj thiab cov txiaj ntsig ntawm laser xim tshem tawm tuaj yeem yog sau ua raws li hauv qab no:
● Cov khoom siv tsawg dua
● Txo cov khib nyiab thib ob
● Tsis muaj kev puas tsuaj rau lub substrate vim yog siv cov kev tswj tsis tau laser
● Zoo dua adhesion vim txo qhov roughness
● nrawm dua li cov txheej txheem ib txwm muaj
● Muaj txiaj ntsig ntau dua li cov txheej txheem ib txwm muaj
Muaj ob txoj hauv kev kom ua tiav laser tu. Qhov thib ib yog laser ablation, qhov twg lub zog siab pulse los yog lub zog nruam nthwv dej yuav ua rau muaj cov ntshav hauv cov txheej txheem, thiab cov plasma poob siab yuav ua rau cov txheej txheem tawg. Qhov thib ob yog thermal decomposition, qhov twg qis-zog nruam nthwv dej beam lossis ntev mem tes tuaj yeem ua kom sov rau saum npoo thiab thaum kawg evaporate txheej.
Txawm li cas los xij, tsis muaj kev tswj hwm lub tshuab laser tuaj yeem ua rau lub substrate puas thiab ua rau muaj teeb meem. Ob leeg nruam thiab mem tes lasers yuav siv tau rau laser tu, tab sis nws yog ib qho tsim nyog yuav tsum nkag siab txog qhov sib txawv ntawm cov lasers tsim ntawm cov substrates sib txawv. Kev nqus ntawm lub laser txuas ntxiv los ntawm lub substrate nyob ntawm nws lub wavelength, nrog luv wavelengths feem ntau ua rau kev nqus ntau dua. Rau ib tug classical pulsed laser, ntawm qhov tod tes, qhov tob tob LT rau hauv lub substrate yog ywj siab ntawm lub wavelength thiab nyob ntawm seb lub mem tes dav τp ntawm lub laser thiab diffusion coefficient D ntawm lub substrate, raws li qhia nyob rau hauv Equation 1.
Rau ib tug classical pulsed laser, ib tug nce nyob rau hauv mem tes dav tsub kom lub ablation pib, uas yog txhais raws li qhov tsawg kawg nkaus lub zog yuav tsum tau tshem tawm ib chav tsev ntim ntawm cov khoom raws li cov nram qab no kab zauv:
qhov twg ρ yog qhov ceev thiab Hv yog qhov kub ntawm vaporization (qhov kub ntawm qhov yuav tsum tau vaporize ib chav tsev ntawm cov khoom hauv Joules ib gram). Yog li, ntev pulses txo cov ablation efficiency. Classical pulsed lasers kuj nyob ntawm seb tus mem tes repetition npaum li cas, qhov twg ablation efficiency nce nrog nce repetition tus nqi.
Ib txoj kev tshawb fawb tau ua los tshawb xyuas CW thiab cov qauv ua haujlwm ntawm lub laser siv 1.07 μm fiber ntau laser [Ref 2]. Hauv txoj kev tshawb no, tib lub CW laser tau hloov mus rau thiab tawm los tsim cov pulses ntev. Txoj kev tshawb no pom tias hauv CW hom, lub zog tshwj xeeb (txhais tau tias yog lub zog yuav tsum tau tshem tawm ib chav ntim ntawm cov khoom (mm3) hauv Joules thiab inversely proportional to the ablation efficiency) txo qis nrog nce scan ceev thiab laser zog. Rau hom mem tes, qhov ablation efficiency tau pom nyob ntawm lub luag haujlwm lub voj voog (qhov piv ntawm lub mem tes dav mus rau lub sijhawm luv ntawm ob lub pulses). Ua kom lub luag haujlwm lub voj voog, qhov ablation efficiency nce. Qhov no yog qhov sib piv rau classical pulsed lasers, qhov twg, ntawm qhov kev rov ua kom ruaj khov, ua rau lub plawv dhia dav (thiab yog li lub voj voog lub luag haujlwm) txo qis kev ua haujlwm ablation. Daim duab 3 piv rau lub zog tshwj xeeb piv rau lub zog thiab kev ntsuas nrawm rau 1 kHz CW laser thiab lub laser pulsed (piv txwv li, CW laser hloov rau thiab tawm) ntawm cov hlau tsis muaj steel substrate.
Lub laser pulsed (piv txwv li, CW laser hloov rau thiab tawm) muaj lub zog siab tshaj plaws ntawm 1800 W thiab lub zog nruab nrab yuav luag zoo ib yam li CW laser, tab sis raws li tau pom los ntawm daim duab, lub zog tshwj xeeb yuav luag 2 zaug qis dua. . Pulsed hom piv rau CW hom. CW hom zoo li muaj kev poob ntau dua li hom mem tes vim tias lub zog laser ib txwm nyob ntawm tus nqi siab tshaj.
Txawm li cas los xij, hom uas lub laser ua haujlwm tsis yog qhov kev txiav txim siab nkaus xwb hauv kev txiav txim siab seb puas yuav siv lub tshuab hluav taws xob (piv txwv li, nruam nthwv dej rau thiab tawm) lossis lub tshuab hluav taws xob txuas ntxiv rau laser tu. Tus qauv scanning yog lwm qhov kev txiav txim siab tseem ceeb. Nws yog ib qho tseem ceeb uas lub sij hawm sib cuam tshuam ntawm lub laser beam thiab txheej yog luv kom cov nyhuv ntawm thermal puas yog tsawg heev. Qhov no tuaj yeem ua tiav los ntawm kev siv cov pulses luv luv nrog kev siv siab siab lossis siv lub laser txuas ntxiv thiab nrawm nrawm nrawm.
Xav txog tias lub zog laser txuas ntxiv yog feem ntau muaj zog dua, pheej yig dua, thiab ntau dua rugged dua li cov lasers pulsed, nws tsis yog qhov kev xaiv phem rau kev tu lub laser. Hmoov tsis zoo, cov galvanometer scanners ib txwm siv rau kev ntxuav laser tsis tuaj yeem tuav ntau-kilowatt lasers. Galvanometer scanners siv rau high-power lasers kuj hnyav heev thiab tsis tuaj yeem khiav ntawm high scanning speeds. Yog li ntawd, ib hom tshiab ntawm scanner hu ua polygon scanner tau thov uas tsuas muaj ib qho txav mus, lub polygon [Reference 3]. Cov tshuab luam ntawv polygon no muaj peev xwm tswj tau lub zog laser siab dua thiab tau pom tias yog peb zaug sai dua li galvanometer scanners. Siv cov kev sib hloov ceev ceev, cov tshuab luam ntawv polygon tuaj yeem tsim qhov nrawm nrawm dua li 50 meters ib ob. Qhov kev soj ntsuam siab ceev no tso cai rau lub sijhawm luv luv ntawm cov nqaj nrog rau qhov chaw ua haujlwm thiab tso cai rau kev siv lub zog laser siab heev. Daim duab 4 qhia qhov tsim ntawm lub tshuab luam ntawv polygon.
Hauv cov ntsiab lus, kev xaiv ntawm kev siv CW lossis laser pulse (piv txwv li, CW lossis classical luv-pulse lasers uas tau hloov thiab tawm) rau kev ntxuav laser nyob ntawm ntau yam, xws li hom substrate, qhov nqus ntawm txheej, thiab tus nqi ntawm lub laser. Kev sib xyaw ua ke ntawm lub tshuab scanner polygon thiab lub laser txuas ntxiv tuaj yeem tsim cov scan nrawm nrawm thiab yog qhov kev xaiv pheej hmoo uas tuaj yeem txiav txim siab thaum classical pulsed lasers tsis muaj.
