热重分析仪测量居里点示值误差的不确定度评定

热重分析仪测量居里点示值误差的不确定度评定Title: Uncertainty Evaluation of Curie Point Value Measurement Errors for Therm

热重分析仪测量居里点示值误差的不确定度评定 Title:UncertaintyEvaluationofCuriePointValue MeasurementErrorsforThermogravimetricAnalyzer Abstract: Thermogravimetricanalysis(TGA)iswidelyusedtomeasure theCuriepointvalueofmaterials.Accuratedeterminationofthe Curiepointvalueiscrucialforunderstandingthethermalbehavior andmagneticpropertiesofmaterials.However,themeasurement errorsanduncertaintiesassociatedwithTGAmeasurementscan significantlyaffectthereliabilityandreproducibilityoftheCurie pointvalue.ThispaperaimstoevaluatetheuncertaintyofCurie pointvaluemeasurementerrorsforTGAbyconsideringvarious sourcesofuncertaintiesandproposingamethodologyfor uncertaintyestimation. 1.Introduction: TheCuriepointisacriticaltemperatureabovewhichcertain materialsundergoaphasetransitionfromaferromagneticor ferrimagnetictoaparamagneticstate.TheCuriepointvalueisan essentialparameterforcharacterizingthemagneticpropertiesof materials.TGAisacommonlyusedtechniquetodeterminethe Curiepointvaluebymeasuringtheweightchangeofasampleas afunctionoftemperature.However,severalfactorsandsourcesof errorscontributetotheoveralluncertaintyofCuriepoint measurements. 2.SourcesofMeasurementErrorsandUncertainty: a)Instrumentation:TheTGAinstrumentitselfcanintroduce errorsduetofactorssuchassensordrift,temperatureuniformity, andcalibrationaccuracy. b)SamplePreparation:Variationsinsamplesize,shape,and compositioncanleadtomeasurementerrors. c)HeatingRate:Theheatingratecanaffecttheaccuracyof theCuriepointdetermination,asnon-uniformheatingorrapid heatingcanintroduceerrors. d)AmbientConditions:Changesinatmosphericpressureand humidityduringthemeasurementcaninfluencetheCuriepoint value.