ga对nbsi合金组织及力学性能的影响-effect of ga on microstructure and mechanical properties of nbsi alloy.docx

下载文档 降价啦

7
0
约4.44万字
约 61页
2018-06-04 发布于上海
举报
版权申诉
保障服务

ga对nbsi合金组织及力学性能的影响-effect of ga on microstructure and mechanical properties of nbsi alloy.docx

1、本文档共61页，可阅读全部内容。
2、有哪些信誉好的足球投注网站（book118）网站文档一经付费（服务费），不意味着购买了该文档的版权，仅供个人/单位学习、研究之用，不得用于商业用途，未经授权，严禁复制、发行、汇编、翻译或者网络传播等，侵权必究。
3、本站所有内容均由合作方或网友上传，本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺！文档内容仅供研究参考，付费前请自行鉴别。如您付费，意味着您自己接受本站规则且自行承担风险，本站不退款、不进行额外附加服务；查看《如何避免下载的几个坑》。如果您已付费下载过本站文档，您可以点击这里二次下载。
4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等，请点击“版权申诉”（推荐），也可以打举报电话：400-050-0827(电话支持时间：9:00-18:30)。

ga对nbsi合金组织及力学性能的影响-effect of ga on microstructure and mechanical properties of nbsi alloy

AbstractInthispaper,westudytheinfluenceoftheGaadditiononmicrostructureandmechanicalpropertyofNb-Sialloy.Westudytheformationofsolidificationmicrostructure of Nb-Sialloy throughOM, XRD andSEM.Wetestandcompare themechanicalpropertyofarcmeltingalloywithdifferentGaadditionandheattreatmentthroughGleeble-1500ThermalSimulator,UniversalTestingMachinesand MicroHardness Tester.ThevolatilecomponentsofArc-meltedNb-16Si-xGaalloyareSiandGa.TheevaporationrateofGaislessthanSi.GaadditiononNb-16SialloyisconducivetothegenerationofNbss+Nb5Si3eutectic.ThemicrostructureofNb-16Si-5GaalloyconsistsofNbss+Nb5Si3eutectic.Theroomtemperaturestrengthandductilityis improvedwithGaadditiononNb-16Sialloy,buttoomuchGawilldecreasetheroomtemperaturestrength.Thevariationofhightemperaturestrengthissimilartothevariationofroomtemperaturestrength.ToosmallNb5Si3cannotprovidesufficientresistancetodeformation.Theroomtemperaturefracturetoughnessof Nb-16Si-xGaalloyincreaseswithGaaddition.SmallNbss+Nb5Si3eutecticstructureisgoodfor thefracturetoughness.WiththeGaadditiononNb-16Si-22Ti-2Hf-2Al-2Cralloy,hypoeutecticcompositionisconvertedintohypereutecticcomposition.Nb3SiisdecreasedandNb5Si3isgraduallyincreased.Theroomtemperaturestrengthandductility,hightemperaturestrengthandroomtemperaturefracturetoughnessisincreasedandthendecreasedwithGaadditiononNb-16Si-22Ti-2Hf-2Al-2Cralloy.Nbss+Nb5Si3eutecticstructureisconducivetothefracturetoughness.Theblocksilicideisnotconducivetothecompressionperformanceof materialsatroom orhightemperature.TheGacausesNb3SiphaseeutectoidtransformationinNb-16-xGaalloyat1250℃.Nbss+Nb5Si3eutecticprovidesthenucleationsubstrateforeutectoidtransformation.Heattreatmentat1250℃for10hourenablesthesilicidephaseofNb-16Si-22Ti-2Hf-2Al-2Cr-xGa alloy to become smaller and round, but Nb3Siphaseeutectoidreaction doesnot occurs.Keywords:Nb-Sialloy，Gaaddition，microstructures，mechanicalproperties，heattreatmentII目录摘要.....................................................................................................