NF E51-240-1991 制冷电动压缩机.容积式密闭电动压缩机组和可维修密闭电动压缩机组.性能说明

上一篇: NF H35-093-1991 制瓶工业.广口玻璃容器.(凸缘瓶口)
下一篇: NF Z43-203-1991 缩微照相.台式缩微阅读器.特性和简化检测方法

【英文标准名称】:StandardTestMethodforMagneticPropertiesofHigh-CoercivityPermanentMagnetMaterialsUsingHysteresigraphs
【原文标准名称】:使用磁滞曲线记录仪测试高矫顽磁力永磁材料磁性的标准试验方法
【标准号】:ASTMA977/A977M-2007
【标准状态】:现行
【国别】:
【发布日期】:2007
【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】:A06.01
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:coercivefieldstrength;coercivity;hysteresigraph;induction;magnetic;magneticmaterial;magnetictest;permanentmagnets;permeameter;remanence
【摘要】:1.1Thistestmethodcovershowtodeterminethemagneticcharacteristicsofmagneticallyhardmaterials(permanentmagnets),particularlytheirinitialmagnetization,demagnetization,andrecoilcurves,andsuchquantitiesastheresidualinduction,coercivefieldstrength,kneefield,energyproduct,andrecoilpermeability.Thistestmethodissuitableforallmaterialsprocessedintobulkmagnetsbyanycommonfabricationtechnique(casting,sintering,rolling,molding,andsoforth),butnotforthinfilmsorformagnetsthatareverysmallorofunusualshape.Uniformityofcomposition,structure,andpropertiesthroughoutthemagnetvolumeisnecessarytoobtainrepeatableresults.Particularattentionispaidtotheproblemsposedbymodernmaterialscombiningveryhighcoercivitywithhighsaturationinduction,suchastherare-earthmagnets,forwhicholdertestmethods(seeTestMethodA341)areunsuitable.AnapplicableinternationalstandardisIECPublication60404-5.1.2Themagneticsystem(circuit)inadeviceormachinegenerallycomprisesflux-conductingandnonmagneticstructuralmemberswithairgapsinadditiontothepermanentmagnet.Thesystembehaviordependsonpropertiesandgeometryofallthesecomponentsandontheoperatingtemperature.Thistestmethoddescribesonlyhowtomeasurethepropertiesofthepermanentmagnetmaterial.Thebasictestmethodincorporatesthemagneticspecimeninamagneticcircuitwithaclosedfluxpath.Testmethodsusingringsamplesorframescomposedentirelyofthemagneticmaterialtobecharacterized,ascommonlyusedformagneticallysoftmaterials,arenotapplicabletopermanentmagnets.1.3ThistestmethodshallbeusedinconjunctionwithPracticeA34/A34M.1.4Thevaluesandequationsstatedincustomary(cgs-emuorinch-pound)orSIunitsaretoberegardedseparatelyasstandard.Withinthistestmethod,SIunitsareshowninbracketsexceptforthesectionsconcerningcalculationswherethereareseparatesectionsfortherespectiveunitsystems.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnonconformancewiththistestmethod.1.5Thenamesandsymbolsofmagneticquantitiesusedinthistestmethod,summarizedinTable1,arethosegenerallyacceptedbytheindustry.1.6ThistestmethodisusefulformagnetmaterialshavingHcivaluesbetweenabout100Oeand35kOe[8kA/mand2.8MA/m],andBrvaluesintheapproximaterangefrom500Gto20kG[50mTto2T].High-coercivityrare-earthmagnettestspecimensmayrequiremuchhighermagnetizingfieldsthaniron-coreelectromagnetscanproduce.Suchsamplesmustbepremagnetizedexternallyandtransferredintothemeasuringyoke.Typicalvaluesofthemagnetizingfields,Hmag,requiredforsaturatingmagnetmaterialsareshowninTableA2.1.1.7Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.
【中国标准分类号】:H21
【国际标准分类号】:29_030
【页数】:12P.;A4
【正文语种】:


【英文标准名称】:Luminaireswithoperatingvoltagesbelow1000V;fixedluminairesforfluorescentlampswithseparatemountedballasts,capacitorsorstartersVDESpecificationdispose