1.0ScopeAmethodfordeterminingwhetherornotthe
powderinasolderpastecomplieswiththerelevantpowder
type.TheASTMB-214standardscreenpowdersizedistribu-
tionmethodhasbeenfoundtobeacceptable.
2.0ApplicableDocuments
ASTME11
BS.410
DIN4188
ISO565
ISO3310
3.0TestSpecimen
Approximately150gramsofsolderpaste
4.0Equipment/Apparatus
Vibratorytestsievingmachine
TestsievestoBS.410,ASTME11,DIN4188,orISO565and
ISO3310withmeshopeningsof150,75,45,38,25and20
micrometers
Sievebottomreceiverandlid
Balance(scale)withanaccuracyof0.01g
Beaker400–600ml
Watchglass
Solvent
Acetone
Spatula
5.0Procedure
5.1Preparation
5.1.1Wait,ifnecessary,untilthesolderpasteisatroom
temperature.
5.2Test
5.2.1Homogenizethepastebystirringwiththespatula.
5.2.2Weighpastecontainingapproximately110gofsolder
alloyintothecarefullycleanedbeaker.
5.2.3Addapproximately50mlsolvent.
5.2.4Stirthemixturewiththespatulasothatthefluxinthe
pastecandissolveinthesolvent.
5.2.5Coverthebeakerwiththewatchglass.
5.2.6Letthebeakerwiththewatchglassstanduntilthe
solderpowdersettles.
5.2.7Decant,carefully,asmuchaspossibleofthefluid
withoutlosinganyofthesolderpowder.
5.2.8Repeattheextractionprocedurefivetimes,using50
mlsolventforeachextraction.
5.2.9Addapproximately50mlacetonetothewashedsol-
derpowderandstirwiththespatulatoassistindrying.
5.2.10Letthesolderpowdersettle.
5.2.11Decant,carefully,asmuchaspossibleofthe
acetone.
5.2.12Repeattheacetonewash2additionaltimes.
5.2.13Allowthepowdertodryatambienttemperatureuntil
theweightisconstant.
5.2.14Weightestsieves,withmeshopeningsizesappro-
priateforthetypeofpowderbeingtested,andthesievebot-
tomreceiver.TypicalsievesrequiredareshowninTable1.
Table1ScreenOpening
Type11507520
Type2754520
Type3452520
Type43820
TheInstituteforInterconnectingandPackagingElectronicCircuits
2215SandersRoad?Northbrook,IL60062
IPC-TM-650
TESTMETHODSMANUAL
Number
2.2.14
Subject
SolderPowderParticleSizeDistribution—Screen
MethodforTypes1-4
Date
1/95
Revision
OriginatingTaskGroup
SolderPasteTaskGroup(5-24b)
MaterialinthisTestMethodsManualwasvoluntarilyestablishedbyTechnicalCommitteesoftheIPC.Thismaterialisadvisoryonly
anditsuseoradaptationisentirelyvoluntary.IPCdisclaimsallliabilityofanykindastotheuse,application,oradaptationofthis
material.Usersarealsowhollyresponsibleforprotectingthemselvesagainstallclaimsorliabilitiesforpatentinfringement.
EquipmentreferencedisfortheconvenienceoftheuseranddoesnotimplyendorsementbytheIPC.
Page1of2
5.2.15Placethesievesonthereceiverwiththesievewith
thesmallestopeningonthereceiverandprocessingsequen-
tiallyupwardtothelargestopeningscreen.
5.2.16Weighthepowderandputthisinthetopsieve.
5.2.17Placethelidonthesievecombinationandtransfer
thistothesievingmachine.
5.2.18Runthemachineforapproximately40minutes.
5.2.19Reweighthesievesandthereceiver.
5.2.20Subtracttheoriginalweightsofthesievesandthe
receivertoobtaintheweightsofpowderwithsizesgreater
than,within,andlessthanthenominalsizerangefromTable
2Aand2B.
5.3EvaluationExpressthemassesofthepowderabove,
within,andbelowthenominalsizerangeaspercentagesof
themassoftheoriginalsample.EnterdatainTable3.
Table2A%ofSamplebyWeight—NominalSizes
LessThan1%
LargerThan
80%Minimum
Between
10%Maximum
LessThan
Type1150Microns150–75Microns20Microns
Type275Microns75–45Microns20Microns
Type345Microns45–25Microns20Microns
Table2B%ofSamplebyWeight—NominalSizes
LessThan1%
LargerThan
90%Minimum
Between
10%Maximum
LessThan
Type438Microns38?20Microns20Microns
Table3
Type1+150μm+75μm+20μm–20μm
Type2+75μm+45μm+20μm–20μm
Type3+45μm+25μm+20μm–20μm
Type4+38μm+20μm–20μm
IPC-TM-650
Number
2.2.14
Subject
SolderPowderParticleSizeDistribution—ScreenMethodfor
Types1-4
Date
1/95
Revision
Page2of2
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