温湿度加速模型讨论

偶然看到一篇文章，里面有关温湿度加速试验的计算，希望大家一起来讨论讨论。

TemperatureCycle/thermalShock(Source:AmkorTech)

[table=439][tr][td=1,1,64]Condition[/td][td=1,2,82]Chamberzones[/td][td=2,1,206]RealisticReliabilityrequirements[/td][td=1,1,87]SpecifiedReliabilityRequirement[/td][/tr][tr][td]Celsius[/td][td=1,1,88]~Iyearlife(cycles)[/td][td=1,1,118]~5yearslife(cycles)[/td][td=1,1,87]cycles[/td][/tr][tr][td]0to100[/td][td=1,4,82]Single
(Slowramp,
2-5C/min)[/td][td]180[/td][td]900[/td][td]1500[/td][/tr][tr][td]-25to100[/td][td]125[/td][td]625[/td][td]700[/td][/tr][tr][td]-40to100[/td][td]120[/td][td]600[/td][td]800[/td][/tr][tr][td]-40to125[/td][td]90[/td][td]450[/td][td]500[/td][/tr][tr][td]-40to85[/td][td=1,4,82]Dual(fastramp,2-3sectransfer)[/td][td]130[/td][td]650[/td][td]300-500[/td][/tr][tr][td]-40to100[/td][td]90[/td][td]450[/td][td]800[/td][/tr][tr][td]-40to125[/td][td]70[/td][td]350[/td][td]500[/td][/tr][tr][td]-55to125[/td][td]60[/td][td]300[/td][td]300[/td][/tr][/table]

TemperatureHumidityTesting(source:MicroelectronicsReliabilityvol42,No8,ISBN0026-2714)
[table=531][tr][td=4,2,352]Properties[/td][td=2,1,179]TestMethods[/td][/tr][tr][td]40oC/95%RH[/td][td]
85oC/85%RH[/td][/tr][tr][td=4,1]ACCF(T)relatedto25oC@Ea=1eV(eqn1)[/td][td]6.5[/td][td]683[/td][/tr][tr][td=4,1]ACCF(RH)relatedto50%RH@X=5(extremecase)[/td][td]24.8[/td][td]14.2[/td][/tr][tr][td=4,1]ACCF(RH)relatedto50%RH@X=2.5
[/td][td]5[/td][td]3.8[/td][/tr][/table]
[table=98%][tr][td=3,1,234]40oC/95%RH[/td][td=1,1,118]testingtime(hours)[/td][td=1,1,87]48[/td][td=1,1,92]500[/td][td=1,1,64]1000[/td][/tr][tr][td=3,1]ACCF(T,Ea=1eV)*ACCF(RH,x=5)[/td][td]equivalent
years[/td][td]0.90[/td][td]9.33[/td][td]18.66[/td][/tr][tr][td=3,1]40oC/95%RH[/td][td]testingtime[/td][td]48[/td][td]500[/td][td]1000[/td][/tr][tr][td=3,1]ACCF(T,Ea=1eV)*ACCF(RH,x=2.5)[/td][td]equivalent
years[/td][td]0.18[/td][td]1.88[/td][td]3.76[/td][/tr][tr][td=3,1]85oC/85%RH[/td][td]testingtime(hours)[/td][td]48[/td][td]500[/td][td]1000[/td][/tr][tr][td=3,1]ACCF(T,Ea=1eV)*ACCF(RH,x=5)[/td][td]equivalent
years[/td][td]53.88[/td][td]561.26[/td][td]1122.52[/td][/tr][tr][td=3,1]85oC/85%RH[/td][td]testingtime[/td][td]48[/td][td]500[/td][td]1000[/td][/tr][tr][td=3,1]ACCF(T,Ea=1eV)*ACCF(RH,x=2.5)[/td][td]equivalent
years[/td][td]14.42[/td][td]150.20[/td][td]300.39[/td][/tr][/table]
ACCF(T)=Lu/La=exp[(Ea/R)(1/Tu-1/Ta)]equation1
ACCF(RH)=[(RHa)/(RHu)]xequation2
ACCF(T,RH)=ACCF(T)*ACCF(RH)equation3

where:
ACCF=accelerationfactor
Lu=Lifeatnormalusecondition
La=lifeatacceleratedcondition
Ea=activationenergy
R=universalgasconstant
Tu=Tempatnormalusecondition
Ta=Tempatacceleratedcondition
RHu-Relativehumidityatnormalusecondition
RHa-Relativehumidityatacceleratedcondition
x=anempirircalextensionbetween2and2.5(basedonPeck’sModel)

ComparisonofthepropertiesoftwoTemperatureHumidityTestmethods

Note:
1.ChoiceofEaaswellasAcceleratedandNormaluseconditionhaveaverylargeeffectontheACCF(T)
2.The85/85methodhashigherACCF(T)whileitsACCF(RH)islower.
3.FailuremechanismsinducedbyTemperatureandRHarefullyindependent