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12 个结果
  • 简介:AmedicalcastCoCrMoalloywascoatedbyplasmanitridingprocesstoenhancethewearresistance.Themicrostructures,phasesandmicro-hardnessofnitridedlayerswereinvestigatedbyatomicforcemicroscopy(AFM),scanningelectronmicroscopy(SEM),X-raydiffraction(XRD)andmicro-hardness.Tribologicalpropertieswereinvestigatedonapin-on-discweartesterunder25%bovineserumsolutions.Theexperimentalresultsshowedthatplasmanitridingwasapromisingprocesstoproducethick,hardandwearresistantlayersonthesurfaceofCoCrMoalloy.TheharderCrNandCr2Nphasesformedontheplasmanitridedlayerwiththecompactnano-crystallinestructure.Comparedwiththeuntreatedsample,allnitridedsamplesshowedthelowerwearratesandhigherwearresistanceatdifferentappliedloadsandnitridingtemperatures.Itwasconcludedthattheimprovementofwearresistancecouldbeascribedtotheformationofthickerandhardernitridedlayerswiththespecificmicrostructuresonnitridedsurfaces.

  • 标签: 英文摘要 材料科学 优秀论文 科技学报
  • 简介:Thedevelopmentofthermalanalysistechniquesforevaluationofcastalloymeltqualityanditscurrentapplicationsinthefoundrywerereviewed.Thecharacteristicsofthecurrentthermalanalysistechniqueswereanalyzed.Anewcomprehensivemethodforcoolingcurverecognitionhasbeenproposed.Theevaluationofcastalloymeltqualitywasrealized.

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  • 简介:由使用焊接电线的镍,焊接弧的以铁酸盐为主要成的可锻的铁的部分熔化地区(PFZ)和焊接金属的机械性质的寒心的趋势上的alloying的效果系统地被学习了。在这个基础上,为以铁酸盐为主要成的可锻的铁(QT400-17)的弧焊的一个新镍电极第一次被开发。它的焊接金属的机械性质能以铁酸盐为主要成的可锻的铁匹配那些。在PFZ的碳化物层(WCL)的宽度显著地被减少,焊接关节有优秀马赫无能,焊接金属有高热的抗碎裂性。(编辑作者摘要)3个裁判员。

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  • 简介:磨擦促使处理(FSP),FSW的一个变化(磨擦促使焊接)能局部地消除的一种新兴的表面工程技术正在扔缺点和精制微观结构,从而改进material.FSP的机械性质能也通过厚度生产有细密纹理的微观结构给予技术包含跳入很快旋转的superplasticity.The,非可消费的工具,包括一根介绍大头针和更大的直径肩膀,进表面然后越过表面穿越工具。大头针和肩膀磨擦加热在从而改进机械性质的处理区域改变谷物结构的表面。这篇论文在微观结构和渗出的演员组的机械性质上论述FSP的效果2285铝合金在三不同喂率viz.10,12和15mm/min.Withfeed速度的增加材料被观察增加了也增加的impactstrength.FSP张力并且有坚硬和韧性价值的增加的收益力量另外。观察详细被列出了并且图片地代表了。

  • 标签: 显微结构 摩擦加工 机械力学 铝合金
  • 简介:位于加拿大温哥华的IBC先进合金公司与伦敦德里的Nu—Cast企业签署了一个无约束理解备忘录(MOU),旨在合作投资航空用铍铝合金铸造件的生产。备忘录描诉了提高IBC现有铍铝合金近终成形的生产产能和生产率的合作框架,双方将通过节约成本及提高物流效率来增加IBC铸造件的市场占有率。

  • 标签: IBC 备忘录 合作 企业 铍铝合金 市场占有率
  • 简介:Toobtainthecompatiblematerialofhighhardnessandhightoughness,Hadfieldsteelmatrixcomposites,reinforcedbyhigh-Crcastironbarsmadeofflux-coredweldingwires,whichwereinsertedintotheHadfieldsteelmelt,wereinvestigated.Themechanicalpropertiesofthreematerials,ie,compositesforas-castandquenching-watercondition,aswellasHadfieldsteel,werecompared.Theresultsshowthatthealloypowderinsideflux-coredweldingwirescanbemeltedbytheheatcapacityofHadfieldsteelmeltandsolidifyintohigh-Crcastironbars.Theimpacttoughnessofthecompositeforquenching-waterconditionishigherthanthatofthecompositeforas-castconditionandislowerthanthatoftheHadfieldsteel,butitcanstillmeettherequirementsofhardnessandtoughnessinindustrialapplication.Regardlessofloadvariation,compositeforquenching-waterconditionshowsbetterwearresistancethanthoseofthecompositeforas-castconditionandHadfieldsteel.ThemodifiedfracturetoughnessandwearresistanceofcompositesareattributedtonotonlythecombiningactionsofHadfieldsteelmatrixandhigh-Crcastironbars,butalsotheeffectofheattreatment.

  • 标签: 钢基复合材料 高铬铸铁 力学性能 微观结构 药芯焊丝
  • 简介:Thispaperreportstheeffectoffrictionstirwelding(FSW)processparametersontensilestrengthofcastLM6aluminiumalloy.Jointsweremadebyusingdierentcombinationsoftoolrotationspeed,weldingspeedandaxialforceeachatfourlevels.Thequalityofweldzonewasinvestigatedusingmacrostructureandmicrostructureanalysis.Tensilestrengthofthejointswereevaluatedandcorrelatedwiththeweldzonehardnessandmicrostructure.Thejointfabricatedusingarotationalspeedof900r/min,aweldingspeedof75mm/minandanaxialforceof3kNshowedsuperiortensilestrengthcomparedwithotherjoints.Thetensilestrengthandmicrohardnessoftheweldedjointsfortheoptimumconditionswere166MPaand64.8Hvrespectively.

  • 标签: 搅拌摩擦焊接 铝合金接头 拉伸强度 工艺参数 合金铸造 抗拉强度
  • 简介:Thedeformationmechanismsandprocessingmapsoftheas-castAl-Zn-Mg-Cu(7075)aluminum(Al)alloywerestudiedandcomparedwiththoseofthehomogenized7075Alalloyinthetemperaturerangeof573–723Kandinthestrainraterangeof10~(-3)–10s~(-1)toexploreapossibilityfordirectlyusingtheascast7075Alalloyasabilletforhotworking.Theas-castandhomogenized7075Alalloyshadsimilargrainsizesandshowedsimilarhigh-temperaturedeformationbehaviors.Theas-cast7075Alalloy,however,exhibitedhigherpowerefficienciesandsmallerunstable?owregionscomparedtothehomogenized7075Alalloybecauseofthepresenceofsecondaryphases(MgZn_2)segregatedatthedendriticinterfacesintheas-castmicrostructure,whichwereformedduringnon-equilibriumsolidi?cation.Thesesegregatedphasesprovidednucleationsitesfordynamicrecoveryorcontinuousdynamicrecrystallization,andasaresulta?neandmorehomogeneous(sub)grainstructurecouldbeobtainedfromtheas-castmicrostructurecomparedtothehomogenizedmicrostructure.Thecurrentworksuggestedthepossibilityandadvantageofusingas-castmicrostructuresforhotworkingofaluminumalloyswithhighcontentofsolutes.

  • 标签: 铝锌镁合金 AL-ZN-MG-CU 铸态组织 加工图 压缩行为 均质
  • 简介:包含长带扔的一条新奇处理线路,预先退火的处理,冷滚动和退火的再结晶被用于Fe-2.6%Si钢改进磁性。当演员组长带的影响在微观结构,质地,降水和磁性上预先退火被电子探查微量分析,传播电子显微镜学,和X光检查衍射分析调查,等等。秒阶段粒子的降水被快速的团结在长带扔期间制止,这被发现。预先退火的缺席导致了大量20-50的出现?nmMnS在最后的退火的表猛抛,它为好谷物和高核心损失负责(4.01?W/kg)由于谷物边界卡住效果。尽管900-1000的微观结构和质地?桴牥椠?潴愠档敩敶甠瑬慲楨桧甠瑬浩瑡?整獮汩?瑳敲杮桴????慐?楷桴畯?慳牣晩捩湩?潦浲'L汩瑩y

  • 标签: 微观结构 退火 磁性 演员 降水 电子显微镜