【英文标准名称】:StandardPracticeforHeatAgingofPlasticsWithoutLoad
【原文标准名称】:通用的玻璃制品齿轮油氧化和热稳定特性的标准实施规程
【标准号】:ASTMD3045-1992(2010)
【标准状态】:现行
【国别】:美国
【发布日期】:1992
【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】:D20.50
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:
【英文主题词】:aging;exposure;heat;heat-aging;thermal-aging;Acceleratedaging/testing--plastics;Heataging;Heatingtests--plastics;Oxidationtesting--plastics;Thermalanalysis(TA)--plastics
【摘要】:Theuseofthispracticepresupposesthatthefailurecriteriaselectedtoevaluatematerials(thatis,thepropertyorpropertiesbeingmeasuredasafunctionofexposuretime)andthedurationoftheexposurecanbeshowntorelatetotheintendeduseofthematerials.Plasticmaterialsexposedtoheatmaybesubjecttomanytypesofphysicalandchemicalchanges.Theseverityoftheexposuresinbothtimeandtemperaturedeterminestheextentandtypeofchangethattakesplace.Aplasticmaterialisnotnecessarilydegradedbyexposuretoelevatedtemperatures,butmaybeunchangedorimproved.However,extendedperiodsofexposureofplasticstoelevatedtemperatureswillgenerallycausesomedegradation,withprogressivechangeinphysicalproperties.Generally,shortexposuresatelevatedtemperaturesmaydriveoutvolatilessuchasmoisture,solvents,orplasticizers,relievemoldingstresses,advancethecureofthermosets,andmaycausesomechangeincoloroftheplasticorcoloringagent,orboth.Normally,additionalshrinkageshouldbeexpectedwithlossofvolatilesoradvanceinpolymerization.Someplasticmaterialsmaybecomebrittleduetolossofplasticizersafterexposureatelevatedtemperatures.Othertypesofplasticsmaybecomesoftandsticky,eitherduetosorptionofvolatilizedplasticizerorduetobreakdownofthepolymer.Thedegreeofchangeobservedwilldependonthepropertymeasured.Differentproperties,mechanicalorelectrical,maynotchangeatthesamerate.Forinstance,thearcresistanceofthermosettingcompoundsimprovesuptothecarbonizationpointofthematerial.Mechanicalproperties,suchasflexuralproperties,aresensitivetoheatdegradationandmaychangeatamorerapidrate.Ultimatepropertiessuchasstrengthorelongationaremoresensitivetodegradationthanbulkpropertiessuchasmodulus,inmostcases.Effectsofexposuremaybequitevariable,especiallywhenspecimensareexposedforlongintervalsoftime.Factorsthataffectthereproducibilityofdataarethedegreeoftemperaturecontroloftheenclosure,humidityoftheoven,airvelocityoverthespecimen,andperiodofexposure.Errorsinexposurearecumulativewithtime.Certainmaterialsaresusceptibletodegradationduetotheinfluenceofhumidityinlong-termheatresistancetests.Materialssusceptibletohydrolysismayundergodegradationwhensubjectedtolong-termheatresistancetests.Itisnottobeinferredthatcomparativematerialrankingisundesirableorunworkable.Onthecontrary,thispracticeisdesignedtoprovidedatawhichcanbeusedforsuchcomparativepurposes.However,thedataobtainedfromthispractice,sinceitdoesnotaccountfortheinfluenceofstressorenvironmentthatisinvolvedinmostreallifeapplications,mustbeusedcautiouslybythedesigner,whomustinevitablymakematerialchoicesusingadditionaldatasuchascreepandcreeprupturethatareconsistentwiththerequirementsofhisspecificapplication.Itispossibleformanytemperatureindexestoexist,infact,oneforeachfailurecriterion.Therefore,foranyapplicationofthetemperatureindextobevalid,thethermalagingprogrammustduplicatetheintendedexposureconditionsoftheendproduct.Ifthematerialisstressedintheendproductinamannernotevaluatedintheagingprogram,thetemperatureindexthusderivedisnotapplicabletotheuseofthematerialinthatproduct.TherecanbeverylargeerrorswhenArrheniusplotsorequationsbasedondatafromexperimentsataseriesoftemperaturesareusedtoestimatetimetoproduceadefinedpropertychangeatsomelowertemperature.Thisestimateoftimetoproducethepropertychangeorx201C;failurex201D;atthelowertemperatureisoftencalledthex201C;
基本信息
| 标准名称： | 锡化学分析方法 铋量的测定 |
| 英文名称： | Methods for chemical analysis of tin-Determination of bismuth content |
| 中标分类： |
冶金 >>
金属化学分析方法 >>
重金属极其合金分析方法 |
| ICS分类： |
冶金 >>
有色金属 >>
其他有色金属及其合金
|
| 替代情况： | GB/T 3260.3-1982 |
| 发布部门： | 国家质量技术监督局 |
| 发布日期： | 2000-08-02 |
| 实施日期： | 2000-01-02 |
| 首发日期： | 1982-06-21 |
| 作废日期： | 1900-01-01 |
| 主管部门： | 中国有色金属工业协会 |
| 归口单位： | 全国有色金属标准化技术委员会 |
| 起草单位： | 云南锡业公司 |
| 出版社： | 中国标准出版社 |
| 出版日期： | 1900-01-01 |
| 页数： | 7页 |
适用范围
本标准规定了锡中铋含量的测定方法。本标准适用于锡中铋含量的测定。测定范围：0.00010%～0.080%。
前言
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引用标准
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所属分类： 冶金 金属化学分析方法 重金属极其合金分析方法 冶金 有色金属 其他有色金属及其合金