电子制造行业中的贴片胶涂布工艺技术要点分析

精品文档-下载后可编辑电子制造行业中的贴片胶涂布工艺技术要点分析Electronicmanufacturingindustryinrubbercoatingtechnologypointspatchanalysis

Riverbinisauspicious

ThedongguanshebacanelectronictechnologyCo.,LTD.Guangdongdongguan

Abstract:

Intheelectronicmanufacturingindustryinsurfaceinstallationcomponents,toavoidcomponentsinwavesolderinghappenedundertheactionofdisplacement,weldingneedbeforethroughgluecoatingpatchtechnology,withpatchgluewillsurfacemountcomponents(SMD)fixedtotheprintedcircuitboard.Therefore,theelectronicmanufacturingindustryinrubbercoatingtechnologypointspatchofanalysisisverynecessary.

Keywords:patchplasticcoatingtechnologypoints

Intheelectronicmanufacturingindustryinrubbercoatingprocesspatch,patchgumselectioniscrucial,anduseandchoosethesuitableviscositypatchgluecoatingmethodofglue,glueinsolidificationprocessofshearstrengthandcuringtemperaturecontroltoensuresmoothsurfacegluesolidifiedpoint,ensurethequalityofcoatingfilmstickalsoplayanimportantrole.

Apatch,thechoiceofglue

Differentcoatingmethodusedtopatchtheviscosityoftheglue,curingtemperatureandcharacteristicparametersofdifferentrequirements,onlychoiceandcoatingmethodtoadaptthepatchglue,meetthetechnologicalperformanceatthesametimesatisfytheSMTproductionprocessneeds,toguaranteethequalityofcoating.

Patchtopayattentiontothefollowingitemchoiceglue,andsomeofthenecessarytesting:

(a)appearance

Thenewpatchtogluetheouterpackingingoodcondition,signvarieties,model,productiondateandtheviscosityindexclear;Colloidexquisiteandnothickbead,noforeignbody,stickyuniform,brightcolor,easytorecognize.

(2)coatingsex

Plasticcoatingisusedmorepatchneedletypetransfer,printingandpressuredropcoating.Useleakplateprintingmethod,thequalityrequirementsofadhesivehigher,itsappearancetoapeakshapetobebeautiful,andgluepointvaluehighyield,goodresistancetoanti-vibrationeffect,buttheoperationeasyoccurrencetrailing;Alsocandoroundheadshapegluepoint,itsyieldvalueislow,thepointglue,donotappeartodelay.Theappearanceoffinepointgluegeometrysizeshapecoefficientscanbecharacterizeditsmeasurement,therubberundersidediameterandgluepointathighwideaspectratio(W/H)at2.7to4.5ispreferred,ifW/Hthansmallistheglueyieldstrengthhigh.Inhighspeedrunningcanusebesmearofpressuredrop.

(3)storageandplaced

1,5℃orsoinpatchglueintheenvironmentofstorage,canincreaseofepoxyresinpatchcouldtheglue.Whenneedtotakeoutwhenusing,firstinthenextroomtemperatureconditionstemperature,backtothetimeofnotlessthan30minutestemperature,cannotheatingmethodtotemperature.

2inroomtemperature25℃,andthegeneralstoretheviscositychangeand30daysofnominalvalueistotesttheservicelifeoftherubberstrips.

3andSMDgluecoatingtothePCBaftertheperiodofyoustillneedareliablefelt,thelongesttimetoplacetwotofourhoursadvisable.

(4)viscosity,beginningwithhighinitialstrength

1,differentprocesscoatingtodemandtheviscosityisdifferent,needtothroughthesimulationtest,findoutasuitableviscosityvalue,andviscosityselectedstandardtestshouldbeconsistentwiththesupplier.Canbeusedwithcollapsingexperimentwithassessmentspreadingpatchglueandrheologicalbehaviorbutalsoearly:itsspreadtomoderatesex,thatistosecureadhesivedegreesofcomponentsofthecementwithwettingability,butnottoodependent,incasethecollapsingtoManLiutoweldingplateleadtoweldingdefects.

2,theevaluationofqualityrubberstripscanbeusedcomponentsshifttest.ThroughthePCBactualpastedifferentelementsandvibrationrotatingPCB,orwillputinconveyingtheonlineoperationPCB,andincreasethevibration,thejitterwillassessitsbeginningwithhighinitialstrength.

(5)theshearstrengthandtheshearstrengthafterwelding

Toensurethecomponentsfromfalloff,needtoglueaftercuringandwavepatchweldingwasthestrengthoftheimpactwavesoldertojudge.ThatistheSMAconnectorforcuringcoolingtoroomtemperature,willbespecialpush-pullrulestestendclosetobeingmeasuredthecomponentsinaend,slowtoforcepushingelement,makethepush-pullrulesandtestedcomponentstoremaininaplane,getthedata;Alsocanuseastickintoinnercircle,setinthemeasuredcomponentssurface,with0~1kgofordinaryDanHuangChenglittlehookintheotherendofnylonropeandgentlypullnyloncord,maintainalevel,getthedataontheDanHuangCheng.

(6),hightemperatureshift

Usuallytherubberinthepatchaftercuringtemperatureathightemperaturedropmechanicalproperties,especiallytheICpackagevulnerabletopinSoICelementpositionmigrationandcomponentsofoff.Thereforeneedtopatchplasticaftercuringhightemperatureresistantthemechanicspropertiestoevaluation.

(7)electricalproperties

Throughthespecialinstrumenttopatchtheelectricalperformancetestadhesivetesting,includingcompression,thesurfaceresistance,volumeresistance,dielectriclossfactor,dielectricconstant,dampandhotinsulationresistanceandelectricalafteramove.

(8)theresistancetomouldsex

RemaininelectronicproductsinthepatchplasticmustadapttothehumidenvironmentorMarineoperationssuchassuchasnormalworkundertheenvironmentofmould.

Second,gluecoating

Gluecoatingofthecoatingandoffsetpointusuallyway.

(a)pointwith

InpatchgluedispensingwiththemachinetonodbesmearPCBboarddesignatedareas,thereishangedlineortrailing.Hanglineordelaytogluethematrixsurfacepatchovercomponentsandlongertothenextpart,causeweldingispoor.

Trailingwiththepatchplasticviscosityandchange,changepressurecanchangethesizeofthegluepoints,soitcanbetogluesystemsomeadjustment,throughthepressureandtimetogluethesizeofthepointandtrailingcontrol.

(2)offsetprinting

WillstickpiecebyscreenprintingprocesssealgluetoPCBdesignatedarea,cannotonlyverystabletocontrolprintingadhesivevolume,stillcanbeinthesamepieceofPCBbyatriponprintingachievedifferentsize,differentshapesofoffset.Buttheoffsetprintingprocessparametersdirectlyinfluencetheoffsetprinting.Notethatthesheet,scraper,printing,printingpressureclearanceandprintingspeed.

1,sheet

Usedtooffsettechnologyofmetalsheetrelativelytheprintingintheneedforaabitthick,appropriatein0.2~1mmorso;Forgluecan'tinthesolderpastetoflowtothePCBautomaticweldingweldingplategathershrinkage,sheetholesizeisalsoshouldbesmallleaksome,butnotlessthanofcomponentsofthepinsize,inordertoavoidexcessivegluecausecomponentsbetweenpinshortcircuit.ForsmallspacingchipPCB,specialattentionshouldpinshortcircuitchip.

2,scraperandprintingclearance

Scraperwithhigherhardnessisappropriate,canusemetalscraper,incase"hollowedout"sheetholeleakageoftheoffsetprinting.

DuringtheperiodofprintingadhesiveiswaspressureinthetemplateundersideandPCBwithinthegapsbetween,gluetherheologyofthedecisionbytemplateandPCBboardofseparationbetweentheslowgumispulledoutandfall,formorbigorsmallconeshape.Therefore,printinggapvalueshouldbesmall,inordertoensurethatthePCBandsheetwiththeprintingprocessbetweennothappenscraperstrippingfollowed.

OnlyinthintemplateandPCB,therearecertainprintinggapbetweenprinting,canachieveveryhighgluepoints.Contactprintingplasticpointwhenhighlyrestrictedtotemplaterelativelysmallthickness,gluepointheightandthicknessofthetemplatealmost,andtemplateandPCBglueagentalmostequaladhesion.So,scraperwillputsuchas1.8mmbiggluepointgluecuttingoff,andsuchas0.8mmofmediumsizegluepoint,itmayappearirregularshape.

InthetemplateandPCBduringtheseparation,templateandlongrubberagent,makeplasticpointheightmorethantemplatethickness.BecauseplasticagentandtemplateoftheadhesioninbettershapethanandPCB,forsuchas0.3~0.6mmsizegluehighpartgluewillstayinwithinthetemplate.Thelowertheheightofthegluepointcanmaintainthegoodconsistency.

3,printingpressureandprintingspeed

Therheologicalpropertiesofglueisgood,sotheprintingspeedcanberelativelyhighsome,butnothightocannotmakeglueinscraperfrontierrolling.Offsetprintingpressureshouldbecontrolledin0.1~1.0kg/cm,makejustscrapesheetsurfaceglue.

Three,gluesolidified

Mostoftheepoxyadhesivepatchinthefurnaceorinfraredheatingfurnacecompleteconvectionheatcurable.

(a)theshearstrengthcontrol

Althoughtheshearstrengthinanycuringtemperaturecuringtimenotbewiththeincreaseandasharprise,butshearforcebutwillbeinthesamecuringconditionswiththeriseofcuringtemperatureincreased.So,topatchhasformedglue,theminimumandmaximumshearstrengthshouldwith1000gand2000gispreferred.

(2)curingtemperaturecontrol

Patchofgluecuringtemperaturedistributionshouldbeconsideredintemperaturerateandthehighesttemperature.Theincreasedrateoftemperatureandpatchofcuringrateisgluepatchplasticformedinthemainfactorsofthepore,thehighesttemperaturecandecideaftercuringadhesionstrengthandthepercentageofcuring.Duringthecuringtemperaturechangefasteasycausepatchplasticappearedinthepore.Intheinfraredfurnaceepoxyadhesivepatchcuringsafetyheatingrateshouldbe0.5℃/s,butthisratemayandsomemanufacturingenvironmentdoesnottietheconveyorbeltspeed.Tomeettherequirementsoftheproductioniftheconveyorbeltspeed,willmaketheheatingrateincreasestoexceedacceptablerange,increasethepatchisformedintheriskofporeglue.Accordingly,needtotherisingrateofcuretimecontroltocuringtemperaturedistributionwouldnotcausethe