【英文标准名称】:StandardSpecificationforAutocatalyticNickelBoronCoatingsforEngineeringUse
【原文标准名称】:工程用自动催化镍硼铸件
【标准号】:ASTMB607-1991(2003)
【标准状态】:现行
【国别】:
【发布日期】:1991
【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】:B08.08.01
【标准类型】:(Specification)
【标准水平】:()
【中文主题词】:镍;硼;金属覆层
【英文主题词】:autocatalytic;aqueous;sodium;checmicals
【摘要】:1.1Nickelboroncoatingsareproducedbyautocatalytic(electroless)depositionfromaqueoussolutions.Thesesolutionscontaineitheranalkylamineboraneorsodiumborohydrideasareducingagent,asourceofnickelions,abuffer,complexant,andcontrolchemicals.1.2Thisstandarddescribestherequirementsforcoatingsofautocatalyticnickelborondepositedfromaqueoussolutionsontosubstratesforengineeringuse.Thespecificationclassifiesthesecoatingsintotwotypes:1.2.1Type1coatingshaveaboroncontentof0.1tolessthan3.5masspercentwiththebalancenickel.1.2.2Type2coatingshaveaboroncontentof3.5to6masspercentandaminimumof90masspercentnickel.1.3Thecoatingsarehardanduniforminthickness,evenonirregularshapedparts,andusedinawiderangeofapplications.1.4Processsolutionsformulatedwithanalkylamineboraneusuallyproducecoatingsthatcontain0.1to3.5%boron.Thincoatingsofthistypeprovidebondabilityandsolderabilityonelectroniccomponentssuchasleadframes,electricalcontacts,andheaders.Tomaintainsolderability,thesecoatingsaregenerallynotheattreated.1.5Processsolutionsformulatedwithsodiumborohydridearestronglyalkalineandarefrequentlyusedtoplatesteelandtitaniumpartstoimpartsurfacehardnessandwearresistanceproperties.Depositsproducedfromtheseprocessescancontain3to5%boronandthalliumorothermetalswhichareusedtostabilizetheplatingsolutionandmodifythecoatingproperties.1.6Thephysicalandmechanicalpropertiesofthesedepositssuchasdensity,hardness,stress,andmeltingpointwillvarywiththeboroncontent.Thevariationofboroncontentalsoaffectsthequantityandstructureofnickelborideprecipitatedduringheattreatment.Intheas-platedconditionthedepositconsistsofapredominantlyamorphousmixtureofnickelandboronwithahardnessofabout700HKN.Whenthedepositisheatedabove300176;Cthenickelcrystallizes,formingnickelclustersofNi(111)andboronprecipitatesasnickelboride,Ni3B(211)and(311),increasingthehardnesstogreaterthan1000HK100forType2coatings.1.7Thenickelboroncoatingsaremicroporousandofferlimitedcorrosionprotection.Theircolumnarstructure,however,isbeneficialinreducingwearbecauseitprovidesameansoftrappinglubricantswithinthesurfaceofthecoatedpart.1.8Thisdocumentdescribesonlyautocatalyticnickelboroncoatingsthathavebeenproducedwithoutuseofexternalelectricsources.1.9ThefollowinghazardscaveatpertainsonlytotheTestMethodssectionofthisspecification:Thisstandarddoesnotpurporttoaddressthesafetyproblemsassociatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.Note18212;ThefollowingAMSstandardsarenotrequirements.Theyarereferencedforinformationonly:AMS2399andAMS2433.
【中国标准分类号】:H62
【国际标准分类号】:25_220_40
【页数】:6P.;A4
【正文语种】: