《REFLOW基本知识》PPT课件.ppt

《《REFLOW基本知识》PPT课件.ppt》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、Reflow基本知识回流焊的定义回流焊的设备P150简介做温度曲线步骤热电偶原理如何放板进炉中回流焊造成的缺陷目录WhatisReflow?AprocessthatmeltsthesolderpasteandmakessolderjointsbetweencomponentleadsandcopperpadsonPCB.什么是回流焊？回流焊就是将焊锡溶化并在元件引脚与线路板上的焊盘之间形成美观、可靠联接的工艺过程元件(Component)焊膏(SolderPaste)印刷线路板(PCB)ReflowedSolderJoint焊点

2、HeatTransferMechanisms(加热的方式)Heattransfermechanisms:Radiation(红外线)Convection(对流)RadiationHeatTransfer(红外线传热)Radiationmakesuseofradiantheattoheattheprocessarea.(通过红外线的辐射来加热各个温区)Coloroftargetcomponents(元件的颜色)Shadowing(明暗)Distanceoftheradiationsource(离发射口的距离)Frequency

3、(频率)ConvectionHeatTransfer(对流传热)Heatiscarriedtothechamberviasomemedia(热量是通过一些媒介传送到各个温区)Usuallyamixtureofgases(通常是一种混合气体)Solectronusesforceconvectionovens(旭电使用的是强制对流形式的炉子)AdvantagesofConvectionHeat(优势)Velocityoftheflow(流通速度快)Efficientheatingpattern(经济的加热形式)Chamberuni

4、formlyheated(受热均匀)Equipment回流焊设备BTUP1501.10个加热区(HeatingZones)2.加热方式－强制对流(ForceConvection)-AirAmplifier3.所用气体－氮气/空气(N2/Air)4.冷却方法－水冷(WaterCoolingSystem)5.1,2区预热(Preheat)6.3,4,5,6,7,8区浸润(Soak)7.9-10区回流焊(Reflow)8.在1,3,5,7,9的Top面上有压力控制传感器9.有4个气体放大器分别在1,2,9,10的Top上Atmosph

5、ereCurtainAssembliesGasAmplifier&FeedPlenumGasFeedPlenumChambersTypicalConvectionReflowProfile30-60sTypicalReflowSolidificationStagesBTUP150Paragon150LayoutFluxCondenserHeatedSection10ZonesDoubleCoolingSectionLipVentExhaustLipVentExhaust150InchesofHeat10ZonesTop/Bott

6、om2CoolingZonesFluxCondenserSafetyLabelsCAUTION!EMOEMERGENCYOFFOREMERGENCYSTOPBUTTON(RedandWhite)CAUTION!Hotinternalsurfaceusecautionwhenopeningthelid.MECHANICALORPINCHPOINTHAZARD(YellowandBlack)TEMPERATUREHAZARD(YellowandBlack)EMERGENCYSTOPBUTTON(YellowandBlack)S

7、afetyLabelsELECRICALHAZARD(RedandBlack)DANGER!Hotinternalsurfaceusecautionwhenopeningthelid.ELECRICALHAZARD(RedandBlack)DANGERHIGHVOLTAGE!CRUSHHAZARD(RedandBlack)ourhands.DANGER!VAPORHAZARD(RedandBlack)DANGER!ThisequipmentcontainsRefractoryCeramicFibers(RCF)thath

8、avebeenidentifiedbytheInternationalAgencyforResearchonCancer(IARC)asapossiblehumancarcinogen(Group 2B).ExposuretoRCFmaybehazardoust