激光焊接原理及實(shí)踐應(yīng)用

激光焊接

LasersWelding

GirishP.Kelkar,Ph.D.激光焊接原理及實(shí)踐應(yīng)用激光LASER受激輻射式光頻放大器的英文第一個(gè)字母的縮寫LightAmplificationbyStimulationofEmittedRadiation激光焊接原理及實(shí)踐應(yīng)用參考資料References激光的工業(yè)應(yīng)用-J.F.ReadyIndustrialApplicationsofLasers,J.F.Ready激光焊接，W.W.DuleyLaserWelding,W.W.Duley激光加工，W.M.SteenLaserMaterialsProcessing,W.M.SteenAWS焊接手冊(cè)，1-4AWSWeldingHandbooks,1-4激光加工手冊(cè)-美國(guó)激光協(xié)會(huì)出版HandbookofLaserMaterialsProcessingPublishedbytheLaserInstituteofAmerica公開的相關(guān)文獻(xiàn)Publishedliterature激光焊接原理及實(shí)踐應(yīng)用請(qǐng)記住…..

Remember…..學(xué)習(xí)需要積極的參與Learningrequiresactiveparticipation不恥下問Feelfreetoaskquestions無(wú)所顧及地提出個(gè)人不同見解Donothesitatetopresentdifferentviewpoints激光焊接原理及實(shí)踐應(yīng)用光Light光是一種電磁輻射Lightiselectro-magneticradiation我們聽不到.Wavesthatyoucannothear可見光的波長(zhǎng)在0.4-0.7微米之間。Visiblefrom0.4-0.7micronwavelength波長(zhǎng)小于0.4微米是紫外線和X光Below0.4–ultraviolettox-rays波長(zhǎng)大于700nm的光為紅外線和微波。Above0.7–infra-redtomicrowaves0.40.7μmμmVisibleGamma x-rayUVIRMicrowaveTVRadio0.01μm0.001μmYAG1μm激光焊接原理及實(shí)踐應(yīng)用光的吸收和顏色

AbsorptionandColor物體的顏色來(lái)源于它反射的光的波長(zhǎng)Colorofanobject(wavelengththatitreflects)顏色和光的波長(zhǎng)是相關(guān)聯(lián)的。Colorisassociatedwithparticularwavelength黑色和白色代表著什么？Whatisthemeaningofblackorwhitecolor?黑色表面吸收了YAG光，而白色在反射了大部分光。BlacksurfacewillabsorbYAGlightwhilewhitewillreflectmostofit激光焊接原理及實(shí)踐應(yīng)用我們?yōu)槭裁葱枰す猓?/p>

WhydoweneedLasers?材料加工需要吸收很強(qiáng)的光。Absorptionformaterialsprocessingrequiresveryintenselight高強(qiáng)度的光可以通過激光聚焦成光束獲得。Intensitycanbegeneratedbyfocusingabeamoflaserlight普通光不能聚焦成很高的能量密度（或足夠小的點(diǎn)）Ordinarylightdoesnotfocusdowntoahighenoughpowerdensity(orsmallenoughspotsize)手持放大鏡可以把太陽(yáng)光聚焦讓紙燃燒但是不能把金屬融化Hand-heldlenscanfocussunlighttosetfiretopaperbutnotenoughtomeltmetal激光焊接原理及實(shí)踐應(yīng)用LightandLasers單頻的（單波長(zhǎng)）Monochromatic(singlewavelength)校準(zhǔn)的（平行光）Collimated(parallel)激光LaserLight普通光OrdinaryLight很多波長(zhǎng)Manywavelengths不平行Notparallel激光焊接原理及實(shí)踐應(yīng)用LightandLasers激光LaserLight 普通光OrdinaryLight激光焊接原理及實(shí)踐應(yīng)用激光的聚焦

FocusingofLasers激光LaserLight普通光OrdinaryLight單頻（單波長(zhǎng)）和校準(zhǔn)（平行）的光可以聚焦成很小的焦點(diǎn)Monochromatic(singlewavelength)andCollimated(parallel)lightcanbefocusedtoaverysmallspot激光焊接原理及實(shí)踐應(yīng)用激光的種類

TypesofLasers激光能量傳輸LaserPowerDelivery連續(xù)波ContinuousWave(CW)脈沖PulsedQ-開關(guān)Q-switched激光頻率LaserFrequencies基頻和倍頻Fundamentalandmultiples激光焊接原理及實(shí)踐應(yīng)用連續(xù)光纖激光

ContinuousWaveFiberLasers激光在光纖中產(chǎn)生Laserlightiscreatedinthefiber可在連續(xù)波和脈沖波中使用CanbeusedinpulsedmodeaswellasCW可以被用于焊接和切割Canbeusedforweldingandcutting激光二極管光LaserDiodeLight激光二極管光LaserDiodeLight光纖Fiber激光焊接原理及實(shí)踐應(yīng)用脈沖YAG激光（焊接）

PulsedYAGLasers(Welding)閃光燈開關(guān)產(chǎn)生脈沖Flashlampturnsonandofftocreatepulses光纖用于傳送激光Fiberisusedtotransmitlaserlight閃光燈（光泵）FlashLamp(OpticalPump)全反鏡100%mirror90%反鏡90%mirror光纖Fiber激光棒LaserRod激光焊接原理及實(shí)踐應(yīng)用脈沖打標(biāo)激光

PulsedMarkingLasersQ-switchingproducesveryshortpulses,10-100nano-secCannotbeusedforweldingLaserlightdelivereddirectly;nofiberFrequencycanbedoubledortripledtogetgreenorUVlightMMRodMirrorsQ-switchGalvoMirrorsFocusLensFrequencyMultiplier(notpresentinallmarkers)激光焊接原理及實(shí)踐應(yīng)用Galvo-光學(xué)器件

Galvo-Optics經(jīng)常用于打標(biāo)。Oftenusedformarkingapplications逐漸受到焊接應(yīng)用的青睞。IsgainingpopularityforweldingapplicationsNutfield,Inc.LaserWJMTechnologies激光焊接原理及實(shí)踐應(yīng)用激光頻率

LaserFrequencies上表只包括了大部分常用的和商業(yè)化的激光器。Tableincludesonlythemostcommonandcommercializedlasers。波長(zhǎng)WavelengthRange激光種類Laser頻率Frequencies(mm)遠(yuǎn)紅外FarIRCO210.64近紅外NearIRNd:YAG1.064可見光VisibleFrequencydoubledYAGCopper-VaporLasers0.5320.510紫外光UVFrequencytripledYAGFrequencyquadrupledYAGExcimer0.3540.2660.15-0.35激光焊接原理及實(shí)踐應(yīng)用脈沖YAG激光焊接典型示意圖

TypicalLayoutforPulsedYAGWeldingLasers鍍膜反光鏡CoatedMirrors激光Laser光纖OpticalFiber聚光頭FocusHead工件Workpiece透鏡Lens注：某些激光不通過光纖直接傳輸。Note:Somelasersaredelivereddirectwithoutfiber激光焊接原理及實(shí)踐應(yīng)用聚焦高度和焦點(diǎn)尺寸

Focusheightandspotsize短焦距透鏡將光束聚焦成更小的點(diǎn)。Shortfocallengthlens(ofgivendiameter)willfocusthebeamtoasmallerspot高的能量密度。HigherenergydensityFocusheightiscriticalduetoshallowdepthoffocusLensprotectionfromworkpiecespatterisimportant短焦距ShortFocalLength長(zhǎng)焦距LongFocalLengthDepthofFocusSpotSize激光焊接原理及實(shí)踐應(yīng)用TimeShareAsinglelasercanbeusedformultipleapplicationsonatimesharedbasis基于同一個(gè)理論,單雷射可以一次性用于多種應(yīng)用.Mostconvenientwithtransmissionthroughopticalfiber通過可見纖維的轉(zhuǎn)換是最方便的.Processingstationscanbeindifferentrooms工作臺(tái)可以放在不同的房間.Mirrors(100%Reflective)全反鏡激光焊接原理及實(shí)踐應(yīng)用EnergyShareLaserenergysplitintomultiplefragments雷射能量分成多個(gè)部分Typicallythreeoutputsforcircumferentialspotwelding典型的是圓周點(diǎn)焊接的3份輸出量Mirrors(PartiallyReflective)反光鏡(部分反光)33% 50%100%30W10W10W10W激光焊接原理及實(shí)踐應(yīng)用TotalInternalReflection完全內(nèi)反射Lightpropagationthroughfibersdependsontotalinternalreflection通過光纖的光線傳播完全取決于完全內(nèi)反射Air空氣Glass玻璃Core核Cladding覆層ProtectiveSheath接地屏蔽激光焊接原理及實(shí)踐應(yīng)用OpticalFibers光學(xué)纖維Singlemodehasverysmallcorediameter,<10microns單模式只有很小的直徑<10微米Usedfortelecommunicationsandnowforfiberlasers用于電訊,現(xiàn)用于光纖激光SIandGIhavecoresfrom0.1mmto1mm單模式和分級(jí)模式的核從0.1mm到1mmHigherdiameterforhigherpowerlevel能量級(jí)別越高直徑越大SteppedIndex(SI)步長(zhǎng)指數(shù)SingleMode單模式GradedIndex(GI)分級(jí)模式IndexProfiles剖面指數(shù)激光焊接原理及實(shí)踐應(yīng)用SIvs.GI單模式vs分級(jí)模式

SIandGImostfrequentlyusedinmaterialsprocessing單模式和分級(jí)模式

多用于材料加工過程.SIoutputis“top-hat”

independentofinput單模式的輸出獨(dú)立于輸入呈大禮帽狀morerobust更有活力GIoutputmorefaithfulrepresentationofinput分級(jí)模式的輸出與輸入呈保持靠近,Cancreateproblemsifinputbeamqualitychanges如果輸入光束的質(zhì)量改變可能會(huì)產(chǎn)生問題.Canmakedeeperwelds/cuts可能焊接/切的更深.Weldprofilescouldchangebasedonfocusheight焦點(diǎn)高度可能產(chǎn)生焊接側(cè)面的變化SIGI0.6AspectRatio縱橫比1.5“TopHat大禮帽狀”WeldProfiles焊接剖面激光焊接原理及實(shí)踐應(yīng)用FiberInputAlignment光纖輸入排列GoodAlignment好的排列Couldburnfiberinputend可能燒焦光線輸入莫端Couldcreateplasmaatfocus在焦點(diǎn)產(chǎn)生等離子體Couldburncladding可能燒傷覆層激光焊接原理及實(shí)踐應(yīng)用SpotSizewithFiber光點(diǎn)直徑帶光纖Spotsizeisanimageoftheoutputcorediameterofthefiber從光點(diǎn)的大小可以反應(yīng)出光纖核直徑的大小Sizedependsonmagnificationofthetwolensesinthefocushead其大小是由鏡頭前的兩個(gè)透鏡來(lái)決定的.OpticalFiber光纖CoreDiameter核直徑SpotSize光點(diǎn)直徑激光焊接原理及實(shí)踐應(yīng)用LaserSafetyCommonSense常識(shí)Doyounotputyourhandindirectpathofalaserbeam不要把手的頭放在雷射光束的路徑中.Donotlookdirectlyatalaserbeam不要直視雷射光束evenatthoselaserpointersbeams!不要看雷射點(diǎn).Donotlookatanylaserprocesswithanakedeye不要用不防護(hù)的肉眼看任何的激光過程.useplasticsafetyglassesforCO2lasers用塑料防護(hù)眼鏡來(lái)防護(hù)CO2雷射.useYAGsafeglassesforYAGoperations在釔鋁石榴石操作中用釔鋁石榴石安全眼鏡激光焊接原理及實(shí)踐應(yīng)用EyeDamageNearUVfromweldingplasmaandUVlasersIfyouseebluishwhiteduringmaterialprocessing,youneedUVprotection;ordinaryplasticsafetyglassesarenotsufficient!如果你在材料加工的過程中看見藍(lán)白的光,你需要UV保護(hù),一般的塑料防護(hù)眼鏡是不起作用的.VisibleandNearIRfromYAGandfrequencydoubledlasersCornea角膜Lens透鏡子Retina視網(wǎng)膜FarUVandFarIRNearUV接近UVVisibleandNearIR激光焊接原理及實(shí)踐應(yīng)用CollateralDamageFumes煙Solvents,grease,etc.fromtheworkpiece溶劑,油脂等,Metaldustcouldbetoxic金屬顆?？赡苡卸?Decompositionproductsofplasticsprocessing(marking,welding,ordrilling)couldalsobetoxic在朔料加工的規(guī)程中的分解產(chǎn)品,(打表,焊接,或者鉆孔)也是有毒的.Installvacuumpumpsandappropriatefilters安裝真空泵和合適的過濾器.NeedspecialTidustcollectorswhenweldingTiinagloveboxformedicaldeviceapplications當(dāng)在用于醫(yī)療器械的手套盒子中焊接鈦的時(shí)候,需要特殊的吸鈦器.激光焊接原理及實(shí)踐應(yīng)用FireHazard火災(zāi)LaserBeamscanhavebeenknowntocausefires鐳射激光能夠引起火災(zāi).Breaksinopticalfiber光纖削弱Makesureopticalfiberisnotwoundtootightly確保光學(xué)纖維不會(huì)太擊傷.LeakageinCO2directopticsLaserbeamwalkingoffworktableontoplasticcoversLaserbeaminteractionwithglovesinaglovebox激光焊接原理及實(shí)踐應(yīng)用Laser-MaterialInteractionForlensandwindows,AandRhavetobesmall對(duì)于透鏡和窗戶,A和R應(yīng)該是小的.Formirrors,Rhastohigh對(duì)于鏡子,R應(yīng)該高一些ForLaser-basedmaterialsprocessing,AhastobehighandRshouldbelow對(duì)于以雷射原理為基礎(chǔ)的材料加工,A要高一些,R應(yīng)該要低一些.IncidentEnergy入射能Reflection反射Absorption吸收Transmission轉(zhuǎn)播I=A+R+T激光焊接原理及實(shí)踐應(yīng)用InitialReflectivityofMetals金屬的初始反射率Greymetals(AgandAl)arereflectivetoallcolorsinvisiblespectrum灰色金屬(AgandAl)對(duì)所有的有色光譜中的顏色都有反射作用.Copperreflectsnearredwavelengthsandabsorbsothers銅在紅色波長(zhǎng)附近反射,在其他中吸收.0.00.20.40.60.81.00.20.40.71.010Wavelength(mm)ReflectivityAgCarbonSteel碳鋼NiCuAlNd:YAGCO2Source:IndustrialLaserApplications-JohnReady激光焊接原理及實(shí)踐應(yīng)用LaserAngle雷射角落Forallweldingapplications,thelasershouldbeangledoffverticaltopreventlaserenergyfromgoingbackintothelasercavityandcausingdamage對(duì)于所有的焊接應(yīng)用,雷射應(yīng)該與角落垂直以防雷射能量回到激光腔,引起損失.5degrees激光焊接原理及實(shí)踐應(yīng)用AbsorptivityofMaterials材料的吸收率Reflectivityisalsoaffectedbysurfaceroughness,surfaceoxides,partgeometry,andweldpoolshape反射率也是由表面光滑度,表面氧化度,;零件幾何,以及焊接池的形狀.%AbsorbedMeltingPoint熔點(diǎn)Temperature溫度2070激光焊接原理及實(shí)踐應(yīng)用LaserWelding鐳射焊接激光焊接原理及實(shí)踐應(yīng)用Configurations結(jié)構(gòu)Gapdimensionsbecomemorecriticalaspartsgetsmaller由于零件尺寸變小,縫隙的尺寸變得更重要ButtWeld對(duì)接焊接Gap<0.1ttCap蓋子Can罐子t激光焊接原理及實(shí)踐應(yīng)用ConfigurationsGapdimensionsbecomemorecriticalaspartsgetsmaller由于零件尺寸變小,縫隙的尺寸變得更重要Canweldmultiplelayers罐子多層焊接LapWeldGap<0.15t激光焊接原理及實(shí)踐應(yīng)用ConfigurationsPreferconfigurationswherethemoltenmaterialflowsintotheweldinsteadofpullingawayfromit最好的形狀是融化的物質(zhì)是流入到焊接而不是脫離焊接.LapWeldLapFilletLapEdge激光焊接原理及實(shí)踐應(yīng)用AnnularWeldsFitupisimportant移動(dòng)的臺(tái)面很重要.Ifgapispresent,stresseswilldeveloptowardstheendoftheweld如果有縫隙,應(yīng)力會(huì)隨著焊接而增大Press-fitpreferred最好有壓配合.激光焊接原理及實(shí)踐應(yīng)用SmallVolumeWeldsAir/gasintheenclosedvolumeduringfinalweldheatsupandtriestoescape空氣在有限的空間里會(huì)隨著焊接的熱量膨脹,并試圖逸出.Cancauseporositytowardstheendoftheweld可能會(huì)在焊接的最后引起多孔.AirPressureIncreasesDuringWelding在焊接餓過程中空氣的壓力增加激光焊接原理及實(shí)踐應(yīng)用PressureRelief卸壓Allowpressurereliefonenclosedvolumes

如下情況需要泄壓Reducecrack-likefeatureswhichmaybecausedbyhighpressuretrappedinside泄壓可以減少像這種由于內(nèi)部壓力過大而引起的類似裂紋的缺陷.激光焊接原理及實(shí)踐應(yīng)用ShieldGasMainfunctionofshieldinggasistoprotectthemoltenmetalfromreactingwithoxygen保護(hù)氣體的保護(hù)作用主要是保護(hù)融化的金屬不與氧氣反應(yīng).Shieldinggasalsohelpsto:保護(hù)氣體也有助于Protectlens/lenscoverfromweldsplatter保護(hù)透鏡,透鏡蓋不受焊接潑濺Controlplasmacloudformation控制等離子霧形成.Washawaymetalvaporsintheplume吹散等離子體中的金屬蒸汽.激光焊接原理及實(shí)踐應(yīng)用ShieldGasWhatisplasma?什么是等離子體Plasmaisionizedgas等離子是離子化氣體Electronsareseparatedfromatoms(metalaswellasshieldinggas)電子與原子分離(金屬和屏蔽氣體)Plasmaisthefourthstateofmatter;otherthreearesolid,liquid,andgas(等離子體是事物的第四種狀態(tài),其他的三種是固體,液體和氣體)Whatisplume?什么是等離子體?Plumeisamixtureofplasmaandmetalvapors等離子體是等離子以及金屬氣體的混合體.Plume激光焊接原理及實(shí)踐應(yīng)用ShieldGasesforYAGLasersHeliumisidealbutveryexpensive氦很理想,但是很昂貴Argongasismostcommonlyused氬氣是最常用的Nitrogencanbeusedforsomealloys氮可以用于一些合金.Someweldsaremadeinair(noshieldinggas)buttheweldsurfaceisnotverysmooth有些焊接在空氣中做(沒有保護(hù)氣體)但是焊接表面不是太順滑Maystillproduceacceptableweldquality可能仍舊能夠產(chǎn)生有效的焊接質(zhì)量.激光焊接原理及實(shí)踐應(yīng)用SootSootisblackcoloreddust,typicallyreferredtoas“soot”thoughitisnotcomposedofcarbon煙是黑色的灰塵,雖然叫煤煙但它不是由碳組成的.“Soot”isafinedustofmetalpowderthatisdepositedfromtheplume煤煙是一種從等離子中沉淀下來(lái)的金屬粉末.Chemicalanalysisof“soot”fromInconel600激光焊接原理及實(shí)踐應(yīng)用ShieldGasConfigurationCoaxial共軸Toohigh–destabilizestheweldpool,increasedporosity太高-動(dòng)搖焊接溶池,引起多孔.Toolow–cancausenegativepressureandpulluptheweldmetal太低-會(huì)引起負(fù)壓力,使融化的金屬突起.Betterforshielding最好屏蔽SideFlow側(cè)流Usefulforsweepingawaytheionizationproducts用于清理等離子體.激光焊接原理及實(shí)踐應(yīng)用PulsedYAG脈沖釔鋁石榴石ImportantParameters重要的參數(shù)Pulse脈沖Width寬度Energy能量Power能量Shape形狀PulseOverlap脈沖交迭SpotSizeandFocus光點(diǎn)和焦點(diǎn)激光焊接原理及實(shí)踐應(yīng)用PulsedYAG脈沖釔鋁石榴石Energy(J)能量=Power(kW)力xWidth寬度(msec)Initialenergypeakhelpsthelaserenergytocouplewiththematerial初始的高能量可以使激光能量與金屬耦合..ProgrammedPulse程序脈沖PeakPowerPulseEnergy脈沖能量PulseWidth脈沖寬度ActualOutput實(shí)際輸出激光焊接原理及實(shí)踐應(yīng)用PulsedYAG脈沖釔鋁石榴石Shortpulseofhighpeakpowercancauseexpulsion高的峰值能量的短脈沖能引起坑.Longpulseoflowpeakpowerwillproduceawiderandshallowerweldbead低頂點(diǎn)能量的長(zhǎng)脈沖會(huì)產(chǎn)生更寬和更淺的焊縫.PowerPulseWidthDeeperPenetration更深穿透GreaterPorosity更多多孔MoreExpulsion/Spatter更多飛濺ShallowerPenetration更淺穿透LessPorosity更少多孔Cleanerweldswithnoporosity更干凈焊接沒有飛濺激光焊接原理及實(shí)踐應(yīng)用Effectofpulsetimeonweldsize脈沖時(shí)間對(duì)焊接尺寸的影響Weldspotdiameterincreasesrapidlyinthefirstfewmilli-seconds;rateofgrowthreduceswithtime焊斑直徑在最初的千分之一秒期間迅速變大,增長(zhǎng)的速度隨著時(shí)間的增長(zhǎng)而降低.

TimeWeldSize激光焊接原理及實(shí)踐應(yīng)用Effectofpulsetimeonpenetration

脈沖時(shí)間對(duì)焊接尺寸的影響Foragivenpeakpower,weldpenetrationstabilizesafteracertainthresholdweldtime對(duì)于指定的能量高峰,焊接深度在一定的焊接時(shí)間后變得穩(wěn)定.Maximumpenetrationisdirectlyproportionaltopeakpower最大的深度是與能量高峰成直接正比的關(guān)系.Aboveacertainthresholdofpower,thelaserwillendupdrilling/cutting/gouginginsteadofwelding在一定能量的之上,雷射將鉆孔,切斷,咆削而不是焊接.TimePenetrationPeakPower1PeakPower2激光焊接原理及實(shí)踐應(yīng)用PulseShaping脈沖形狀Singlepulseorthreesectorpulseofferedbycapacitorbasedpowersupplies由電源電容器產(chǎn)生的單脈沖和三個(gè)脈沖Newermachinesofferinvertertechnologywithcontinuouspulseshaping更新的提出的能夠提供無(wú)間斷的脈沖形狀.Time(msec)PeakPowerEnergy(J)能量=Power(kW)力xTime時(shí)間(msec)Single單個(gè)Three-sector三部分 Multi-sector多部分激光焊接原理及實(shí)踐應(yīng)用WeldCracking焊接破裂Canisanchoredinthecapwhilecansurfacehasleverage罐子被錨在夾具中,而罐子的表面有杠桿作用.Weldcoolingalwaysintroducesresidualstresses焊接冷卻往往引起殘余壓力.Combinationoflargeweldvolumeandrapidcoolingcanintroduceexcessiveresidualstressesthatcausecracking大量焊接加之迅速冷卻能產(chǎn)生過量的殘余壓力從而引起破裂.Can罐子(AnchoredinClamp錨在夾具中)激光焊接原理及實(shí)踐應(yīng)用LaserFeatures:PulseShape雷射特征:脈沖形狀MeltingandPenetrationPulse溶解滲透脈沖(CouplingPulse偶合脈沖)StabilizationPulse穩(wěn)定脈沖(controlledcoolingtoreduceexpulsionandresidualstresses控制冷卻減少殘余應(yīng)力.)6.0kW0.50.51.0 2.0m-sec50%30%0.2激光焊接原理及實(shí)踐應(yīng)用PulseShaping脈沖形狀Modifiedpulsegavetimefortheweldtocoolslowlyandallowthepore

toriseabovetheweldinterface改良脈沖使焊接冷卻的時(shí)間變慢,而且使得氣孔有時(shí)間從熔融的金屬中上升到表面SquarePulse方形脈沖Modified改良的激光焊接原理及實(shí)踐應(yīng)用FocusHeight焦點(diǎn)高度Atfocus,spotsizenotsensitivetofocusheight在焦點(diǎn),點(diǎn)大小與焦點(diǎn)高度不相互影響.Atfocus,plumeistallestandsoundishighestpitch在焦點(diǎn),等離子體是最高的,而且聲音也是最高調(diào)的.usedtofindfocusheight用于找出焦點(diǎn)高度.Focususuallysetatthesurfaceforpulsedwelding焦點(diǎn)通常設(shè)在表面為脈沖焊接.Focussetbelowsurfacefordeeperpenetrationandkeyholemodewelding焦點(diǎn)射在表面以下為更深的穿透和縮定焊接激光焊接原理及實(shí)踐應(yīng)用PulseOverlap脈沖交疊Dependsonthicknessofcomponentontopandshapeofweldbead取決于零件上端的厚度和焊縫的形狀.Overlapshouldbegreaterbyasafemargin在一定安全范圍之內(nèi),交疊會(huì)大一些.Note:Excessiveoverlapisexcessunwantedheatintotheweld注意:過量的交疊是過度的熱量在焊接中出現(xiàn).Non-hermeticOverlap不密封交疊HermeticOverlap密封交疊激光焊接原理及實(shí)踐應(yīng)用PulseOverlap脈沖重疊Lapweldsrequirehigheroverlap重疊焊接要求更高的重疊Buttweldscanbehermeticevenat50%overlap對(duì)接焊接可以被密封,即便是50%的重疊ButtWeld對(duì)接焊接LapWeld重疊焊接ButtWeld對(duì)接焊接激光焊接原理及實(shí)踐應(yīng)用LaserWeldQuality雷射焊接質(zhì)量WeldSurfaceInspection焊接表面檢測(cè)Weldsurfaceshouldbecleanandfreeofspatter焊接表面需干凈,沒有滴濺Novisiblecracksorholes沒有可見的裂縫和孔.GoodNotGood激光焊接原理及實(shí)踐應(yīng)用LaserWeldQuality雷射焊接質(zhì)量MechanicalTesting機(jī)械測(cè)試BurstStrength爆發(fā)力量PulltestorShearTest拉力測(cè)試和剪切測(cè)試LeakTest測(cè)漏測(cè)試StrengthAnalysis;力量分析Itisveryimportanttokeeptrackofwhereandwhenthefailuresoccurredduringtesting在測(cè)試中,記錄在那里和什么時(shí)候失敗是十分重要的Marklocationsoffailureforfurtheranalysis在失敗的地方做標(biāo)識(shí)是以便將來(lái)進(jìn)一步分析激光焊接原理及實(shí)踐應(yīng)用WeldSectionAnalysis焊接部分分析CrackedWeld焊接破裂SmallPressureBubble?小壓力泡沫GoodWeld好焊接激光焊接原理及實(shí)踐應(yīng)用X-rayAnalysisX-RAY分析Cracksgrowatanangleandappearasstraightlinesinthex-ray(shallowweldonright)[破裂在一個(gè)角中擴(kuò)大,在X-RAY中顯示為一條直線Smallporositiesmaybedifficulttoseeinsuchimages在這樣的圖片中很難看到小孔.Checkforalignment查看齊邊.WeldCrack焊接破裂ShallowWeld焊接陰影Alignment激光焊接原理及實(shí)踐應(yīng)用X-rayimagesofgoodweldsX-RAY中好的焊接激光焊接原理及實(shí)踐應(yīng)用LaserMaintenance雷射維護(hù)Feedbackmonitoronlycheckslasercavityperformance–doesnotcheckpoweratweld反饋器只查看激光腔的性能-不會(huì)查看焊接時(shí)候的能量LaserCavity激光腔FocusHead焦點(diǎn)頭EnergyMeter,BurnMarks,Plexiglas,etc.能量劑,火刺,樹脂玻璃Lens透鏡FeedbackMonitor監(jiān)視器反饋激光焊接原理及實(shí)踐應(yīng)用EnergyMeters能量計(jì)JouleMeters焦耳Setforsinglepulseoraverageovermultiplepulses定為單脈沖或者平均大于多脈沖Shouldbeusedperiodicallytoconfirmenergyattheweld在焊接的時(shí)候周期性的確認(rèn)能量Automationsystemcanbesetformeasurementatwarmupandafterse