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【英文标准名称】:StandardPracticeforCalibrationofTemperatureScaleforThermogravimetry
【原文标准名称】:热解重量测定用温标校准的标准实施规程
【标准号】:ASTME1582-2004
【标准状态】:现行
【国别】:
【发布日期】:2004
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E37.01
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:实施规程;校正;试验;跌落试验;温度;仪表刻度
【英文主题词】:CuriePointstandards;magnetictransitionstandards;meltingpointstandards;temperaturecalibration;thermogravimetry
【摘要】:Thermogravimetricanalyzersareusedtocharacterizeabroadrangeofmaterials.Inmostcases,oneofthedesiredvaluestobeassignedinthermogravimetricmeasurementsisthetemperatureatwhichsignificantchangesinspecimenmassoccur.Therefore,thetemperatureaxis(abscissa)ofallapparent-mass-changecurvesmustbecalibratedaccurately,eitherbydirectreadingofatemperaturesensor,orbyadjustingtheprogrammertemperaturetomatchtheactualtemperatureoverthetemperaturerangeofinterest.Inthelattercase,thisisaccomplishedbytheuseofeithermeltingpointormagnetictransitionstandards.Thispracticepermitsinterlaboratorycomparisonandintralaboratorycorrelationofinstrumentaltemperaturescaledata.1.1Thispracticedescribethetemperaturecalibrationofthermogravimetricanalyzersoverthetemperaturerangefrom25to1500176;Candisapplicabletocommercialandcustom-builtapparatus.Thiscalibrationmaybeaccomplishedbytheuseofeithermeltingpointstandardsormagnetictransitionstandards.1.2Themasschangecurveinthermogravimetryresultsfromanumberofinfluences,someofwhicharecharacteristicofthespecimenholderassemblyandatmosphereratherthanthespecimen.Thevariationsfrominstrumenttoinstrumentoccurinthepointofmeasurementofthetemperature,thenatureofthematerial,itssizeandpacking,thegeometryandcompositionofthespecimencontainer,thegeometryanddesignofthefurnace,andtheaccuracyandsensitivityofthetemperaturesensoranddisplayingscales.Theseallcontributetodifferencesinmeasuredtemperatures,whichmayexceed20176;C.Inaddition,somesampleholderassemblieswillshowvariationsofmeasuredtemperaturewithsamplesizeorheating/coolingrate,orboth.Sinceitisneitherpracticalnoradvisabletostandardizesampleholdersorthermobalancegeometries,instrumentsmaybecalibratedbymeasurementofthedeviationofameltingormagnetic(CuriePoint)transitiontemperaturefromthestandardreferencetemperature.Thisdeviationcanbeappliedasacorrectiontermtosubsequentmeasurements.1.3Thispracticeassumesthattheindicatedtemperatureoftheinstrumentislinearovertherangedefinedbyatwo-pointcalibrationandthatthislinearityhasbeenverified.Thesetwocalibrationtemperaturesshouldbeasclosetotheexperimentalmeasurementstobemadeaspossible.1.4Thispracticedescribesthreeproceduresfortemperaturecalibrationofthermogravimetricanalyzersusinganytypebalance.ProceduresAandBusemeltingpointstandardswithverticalandhorizontalbalances.ProcedureCusesmagnetictransitionstandardsforcalibration.ProcedureAisdesignedspecificallyforusewithhorizontal-typebalancesusingexternalfurnaces.ProcedureBisdesignedspecificallyforusewithverticalhang-downbalancesusingeitherinternalorexternalfurnaces.Noprocedureisrestrictedtotheuseofthefurnacetypedescribedinthatprocedure.1.5Computerorelectronic-basedinstruments,techniques,ordatatreatmentequivalenttothisproceduremaybeused.Note18212;Sinceallelectronicdatatreatmentsarenotequivalent,theusershallverifyequivalencypriortouse.1.6Thedatageneratedbytheseprocedurescanbeusedtocorrectthetemperaturescaleoftheinstrumentbyeitherapositiveornegativeamountusingeitheratwo-pointtemperaturecalibrationprocedureoramulti-pointtemperaturecalibrationwithbestlinefitforthegenerateddata.Note28212;Asingle-pointcalibrationmaybeusedwherethisistheonlyprocedurepossibleorpractical.Theuseofasingle-pointprocedureisnotrecommended.1.7SIunitsarestandard.1.8ThispracticeisrelatedtoISO11358butprovidesinformationandmethodsnotfoundinISO11358.1.9Thisstandarddoesnotpurporttoad......
【中国标准分类号】:N11
【国际标准分类号】:17_200_20
【页数】:9P.;A4
【正文语种】: