DwellTimeThestabilizationtemperaturetimeplusthesoaktemperaturetime.
DynamicTestVoltageorVibrationorShockTesting.
EyringMathematicalmodelusedtorelatebehaviorofanitematonestressleveltoitsbehavioratanotherstresslevel.TheEyringequationmodelallows2variableswhereastheArrheniusequationmodelonlyallows1variable.
ExtrinsicEffectAfailureintheproductduetocausesoutsideoftheproducti.e.,chambervibrationortemperature.
FailureTheterminationofthecapabilityofapartorcomponenttoperformitsfunction.
FailureMechanismThespecificcauseoffailure.
FailureModeThespecificcauseoffailureatthemacroscopiclevel.
FailureRepetitionTherepetitionofafailureinaproductwhenthetestisrepeated.
FatigueThemechanicalfailureofapartwhichhasbeensubjectedtorepeatedreversebendingcycles.
FatigueLifeThespecificnumberofcyclestofailbyrepeatedreversestressing.
FieldFailureAdefectwhichisfoundinasystemusedinthefield.
FixedResonanceVibrationatafixedfrequencycorrespondingtothenaturalfrequencyoftheunitundertest.Dwell
FixtureAdevicewhichisusedtoattachaUUTtoaESSchamberfloorortableforvibrationortemperaturecycling.
FlatpackAsemiconductordevicethathasleadsextendingfromeachedgeoutward.
FlipChipAchipthathasbumpedterminationsspacedaroundthedeviceandisintendedforfacedownmounting.
ForcedVibrationAforcedoscillatoryexcitationonasystem.
GrandMeanEffectThemainvariationinfunctionalityofaproductduetoallsourcesofinputinastresstest.
GullWingAcommonleadformandshapeusedtointerconnectusedtomountsurfacemountdevicestoCCA’s.
HardFailureAfailureinacomponentorsystemwhichiscatastrophicandcannolongeroperate.Ifthecomponentorsystemissubjectedtoanexcessivestressenvironment,theenvironmentmay"kill"thesystemtherebycausingahardfailure.
HarmonicAintegralmultiplevalueofthenaturalfrequencyofasysteme.g.,ifFn=60Hz,thentheharmonicsareHFn's=60,120,180,..Hz.
HermeticityTestAleaktesttodetermineifthetestpackageissealed.
IntermittentAcomponentfailurewhichisnotconsistentandmaylastforaveryshorttime.Theintermittentfailuredoesnotfailatthesametimeandinputlevelusually.
InfantMortalityEarlyfailuresduetolatentdefectsresultingfrommanufacturingerrors.
IntrinsicEffectAfailureresultingfromcausesinternaltotheproduct(weaknessindesign).
InversePowerLawAnacceleratedtestmodelusedtoanalyzethereductionoflifeofaproductwithincreasestress.
IRReflowInfraredreflow.Atechniquetomeltsolderusinglongwavelengthlight.
IsolationTheseparationofvibrationfromstructuresuchthatthestructuredoesnotfeelthevibration.
IsolatorAdevicewhichdoesnotallowvibrationtobetransmittedfromthesourcetothesupport.
JerkRateofchangeofacceleration.
JunctionTempThemaximumallowabletemperatureofamicro-electronicdevice.OperatingattheJunctiontemperaturewillcauseearlyfailure.OperatingneartheJunctiontemperaturewilllowerMTBF.
LaminarFlowLowspeedairflowwhichissmoothandwhereairstreamsdonotcrossormix.Reynoldsnumberlessthan2100.NotdesiredinHALTorHASSairflowtests.
LatentDefectAdefectinapartoritemthatwouldeventuallypreventitfrommeetingitsfunctionalrequirementwhenoperatingwithinitsspecifiedenvironmentandwithinitsspecifiedlifetime.Thistypeflawisnotnormallyobviousandcannotbeseenwiththenakedeye.
LevelTheamplitudeofatestcondition.
LevelofScreenTheamplitudeofRVSSwhichaunitissubjectedorthetemperaturedifferentialofTCSS.
LowPassFilterThefilteringeffectofasystemwhichallowslowfrequencyeffectsbutdoesnotallowhighfrequencyeffects.ACCAhasthisphenomenon.
MassParticipationFactorTheoscillationofapartinasystemthatmovesinadifferentdirectionthanthedirectionofvibrationexcitation.Themassparticipationfactoristhepercentageofthemassanditsvector.
MfgDefectAflawcausedbyin-processerrorsoruncontrolledconditionsduringassembly,test,inspection,orhandling.
MeanTheaveragevalueofasetofvalues.
Miner’sLawThephysicsoffatiguewhereeachmaterialhasaparticularcurveforfatiguestressfailurevs.numberofreversestresscyclestofail.
MixedModeTest2Interpretations.#1)Vibrationofaproductattheprimarymodeandvariousharmonicsoftheprimarymode.#2)Vibrationandtemperaturetesting.
ModeThenaturalfrequencyofasystemorharmonicofthenaturalfrequency.
ModalAnalysisAnanalysistodeterminethenaturalfrequenciesofasystem.Theanalysismaybearealtestoracalculation.
NarrowBandPowerspectraldensityhavingapeakvaluewithinanarrowbandoffrequency.
NAVMATNavalMaterialsCommand.AnobsoletebranchoftheU.S.NavywhichwasformerlyinchargeofNavysystemsqualityandspecifyingESStestingforNavalsystems.TestingguidelinelevelswereestablishedforvibrationandTemperatureCyclingprofilesforESS(calledNAVMATlevels).Nolongerusedbyanydefensevendors.ThestartofESSincommercialworkwasduetotheeffortsofNAVMATin1983.ManytechpapersstillrefertoNAVMATlevelsforcomparisontonewtechnology.TheNAVMATrandomvibrationlevelwas6GRMSforallitems.NAVMATwasdisestablishedintheearly90's.
ModeGeneraltermforthenaturalfrequencyofasystem.Mostsystemshaveseveralmodes.Thefirstmode(ornaturalfrequency)usuallyisthemostdamagingtoasystem.
ModelingThescienceoffailurepredictionbymodelingtheproductandtheanalyzingtheweaknessesinthedesign.NodeThepartorpointofasystemwhichdoesnotmoveduringvibrationexcitation.
Omni-AxialRefersto6DoFvibrationsystemwherethevibrationvectorsareineverydirectionoftheglobe.
OperatingLimitThelevelofvibrationortemperatureatwhichasystemwillnolongeroperatebutwhichwilloperateagainifthestresslevelisreduced.PartInmostcases,anonrepairable,throwaway,electrical/electronicitem.
PatentDefectAflawinapartoritemthatisobviousandcanbedetectedbynormalvisualinspectione.g.,brokenleadwires,crackedcasing,solderballs,workmanshiperrors,etc.
PeaktoPeakThedifferenceinvaluesofthemaximaandtheminimainacurve.
Physics-of-FailureAfailureanalysistodeterminetherootcauseoffailure(failuremechanism)
PickupTransducer(accelerometer,pressure,etc.)
PINDTestingParticleImpactNoiseDetectionTest.Anamplifiedacousticaltestusingelectro-mechanicalmethodsfordetectinglooseparticlesinthecavityofanelectronicdevice.(Rarelyused).
PitchThenominalcentertocenterdistancefromoneconductortracetoanother.
PlannedObsolescenceReferstoaproductthathasanintrinsicallydesignedwearoutperiode.g.,PO=2years.PrePregAdhesivesheetusedtocementMultilayersheetstogetherundertemperature&highpressure.
ProbabilisticReliabilityReliabilityanalysisbasedonstatisticalconsiderationswithoutconsiderationofthestructuraldesignfeatures.
ProcessAfunctionorseriesoffunctionstoproduceadesiredgoale.g.,aprocesstosurfacedefects.
ProfileThegraphoftheinputorresponsecurve(InputProfilee.g.,InputPSDortemperaturegraph);(ResponseProfilee.g.,ResponsePSDorTemperaturegraph).
Quasi-RandomOscillatorymotionwhichisnotsinusoidalandisnotpredictable.OnlytheenergylevelVibrationG^2/Hziscontrollableoverawidebandfrequencyspectrum.(nearlypurerandom).
RandomonRandomAspectrumwhichcontainsarandomvibrationspectraoveranotherrandomvibrationbasewhichisusuallyatalowerlevel.RealEstateSurfaceareaavailableformountingcomponentsonaCCA.
ReliabilityQualityorsurvivabilityofaproductovertime.
ReliabilityGrowthImprovementinreliabilityofaproductbytestingandcorrectionofcausesofdefects.
ReluctanceThermalreluctance.Referstoslowchangingtemperatureofaproductduetoitshighmass.Ahighthermalreluctancepartcannotkeeppacewiththechambertemperaturechanges.ReturnsReferstoreturnofproductstothesellerduetodefectsorfailures.
RobustnessStrengthofaproduct.Abilitytowithstandstress.
RoomConstantThevalueofnoiseinaroomwithanoisesource.Theroomconstantdependsonthesizeandvolumeoftheroom.Thesmallertheroomthehighertheroomconstantnoiselevelsincethewalls,ceilingandfloorwillreflectthenoise.ScreenStrengthTheamplitudeoftheinputvibrationlevelorthemaximumTemperaturedifferenceoftheTCSSprofile.Defectssurfacedareproportionaltoscreenstrength.
ShockResponseAplotofthemaximumresponseexperiencedbya1DoFvibrationsystem(product)asaSpectra(SRS)functionofitsownnaturalfrequencyinresponsetoanappliedshockorrandomvibration(tabtable.UsuallyG'svs.Frequency.
SigmaThestatisticaldeviationfromthemean.
SineonRandomAspectrumcontainsalargenarrowbandfrequencyspike(Sine)inthespectrumoverawidebandrandomvibrationspectrum.
SkewTheamountofasymmetryinastatisticaldistribution.
SoakTimeThetimeallowedforsoakingupheatatagiventemperature.Immediatelyafterstabilizationtime
SoftFailureAtemporaryfailureinacomponentorsystem.Anoncriticalfailure.
SpectrumTheshapeofavibrationinputorresponsecurve.G’sorPSDvs.Frequency.
StabilizationTimeThetimeittakesforaparttoattain95%ofsteadystatetemperature.Startingfromthetimetheinputprofiletemperaturebeginsitsflat(constant)level.
StressTheeffectonanitemwhenforceisapplied.Stresscausestension,warping,bending,stretching,temperaturerise,breaking,etc.Thehigherthestress,theclosertofailure.Allpartsandmaterialshavestresslimits.
StepStressAnacceleratedtestinwhichthelevelsofstressareincreasedinastepwisefashiontocausefailureorfindtheoperatinglimitofaproduct.
StressReliefReductionofstressinbendingorpullingbyasimplecurlorloopinawire.
StressScreeningApplicationofstressfulenvironmentonaproducttosurfaceweaknessesanddefects.
Stress-StrengthFailureAfailurecausedwhentheappliedstressexceedsthestrengthofaproduct.
SubAssemblyAnelectricalassemblythatfitsintoalargerelectricalassembly.
SystemAgroupofunitsinterconnectedorassembledtoperformanoverallelectronicfunction.
TestAspecificevaluationofaUUTunderspecifiedexaminationconditionswhichwillleadtoproofordisproofofitsacceptancetoperforminagivenenvironment.
TaguchiMethodAStatisticalmethodofpredictingthereliabilityofasystem.
TechnologyLimitSeeDestructLimit.Alsocalleddesignlimit.
ThermalCycleTheinputprofilewhichrisesandfallsinaspecifiedtimebutwhichendsatthesametemperaturethatitbegan.
Thermocouple(T/C).Dissimilarpairofmetallicwiresusedtomeasuretemperature.
ThermalShockTherateofchangeofenvironmentalchambertemperature.LowShock,RR<35°C/Minute;Highshock,RR>50°C/Minute;Veryhighshock,RR>100°C/Minute.
TimeHistoryPlotAgraphorplotofthedataforinputorresponseforamplitudevs.time.
TimeConstantThetimeittakesforanexponentialfunctiontoattain63%ofitssteadystatevalue.Thefunctionwillattain95%ofsteadystateinthreetimeconstants(3xTc).Normallyreferredtointemperaturetestingorelectricaltesting.
TopAssemblyHighestlevelofanelectricalassembly.Allsubassembliesfitintothetopassembly.
TrackedResonanceNearlythesameasFixedResonanceFrequencywithexceptionthattheshakerisprogrammed.
TurbulentAirFlowHighspeedairflowwherethestreamlinesmixandcrossandwheretheflowisturbulent.
FrequencyCyclespersecond(Hertz,Hz).Naturalfrequencyistheselfgeneratedoscillationofapartorsystem.Appliedfrequencyistheappliedoscillationtoapartfromanoutsidesource.
UndershootSimilartoOvershootexceptthatitisthemarginundertheTh.Usuallycausedbyinsufficientdwelltime.UpgradingChangingthedesignspecificationtoahigherlevelduetodesignimprovements.
UpratingChangingthedesignspecificationtoahigherlevelduetoabilitytowithstandhighertestlevels.
ViaHoleAverysmallholeincircuitcardassemblyusedforpassingcurrentfromonesideofthecardtoanother.Itisnotusedformountingcomponents.Usuallysolderedthrough.
VibratorThepneumaticpistonassemblythatproducestherandomvibrationinapneumaticvibrationsystembyfastactingrepeatedshocks.
WearoutThelastphaseofthelifetimeoftheproduct.
WeibullWeibulldistribution.Variousplotsoffailure(%defectsfound)datavs.time,MTBF,etc.
What-IfexperimentsAcceleratedstressexperimentsdesignedtofinddefectsandweaknesseswhentheproductisoperatedin“outofbounds”electricalconditionse.g.,What-ifthevoltageishigherorlowerthanthespecduringthestresstest?
WhiteNoisePureornearlypurePowerspectraldensityataconstantvaluewithlittleornochangeoverafrequencyspectrum.
WideBandPowerspectraldensityhavingavalueswithinawidebandoffrequency.
YieldStrengthThestrengthofamaterialwhichafterhavingbeenstressedtoaspecificvalueofstresswillnotreturntoitsoriginalshapeorsize. 好资料，看来要下下来慢慢学习学习了。
英文的看得就更慢了。 刚来几天，收获不小。
回复 #5 zxy1971 的帖子
没有声望不能下载，555 我已经打印出来了，有所了解。不慎感激。 下载了，要慢慢看了! 下载了，要慢慢看了!请教HALT振动与普通单轴的振动有什么区别
请教HALT振动与普通单轴的振动有什么区别?回复 #1 arvinghchen 的帖子
试着回答下你的问题。区别1：HALT的振动是一个三轴六自由度的振动，即三个轴向X,Y,Z及绕三个轴旋转的方向。而单轴的振动当然就只是一个单自由度的振动。
区别2：HALT振动是由气锤装置产生的一个随机振动，频率一般取5-5khz,频率是不可以控制的,可以通过频谱分析仪查看你所要观察的频率 段。单轴的振动一般有电磁式，液压式等，有正弦和随机振动之分，频率是可以控制的。
区别3：HALT控制的只是5-5khz加速度均方根值（Grms)的大小对产品的影响，没有位移值。单轴振动可以控制加速度的峰值，位移的峰值及 随机振动的Grms等。
目前就想到这么多，希望后来的高手再补充！
谢谢！ 显然，楼上的解释的很专业。
区别3以前还真没怎么注意过。
其它的高手也来补充一下。