学科分类
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16 个结果
  • 简介:C92200铜合金是一种Cu-Sn-Zn-Pb系合金,是锡青铜的一种,过去被称为“M”海军青铜与蒸汽装置青铜,有着悠久的历史,获得广泛应用,典型用途:阀和法兰铸件,油泵、齿轮、衬套、轴承、巴氏合金衬管轴管轴承,以及温度Q90℃,压力≤20N/mm2的压力容器零配件。

  • 标签: 锡青铜 海军 材料 海洋 压力容器 蒸汽装置
  • 简介:WehavestudiedtheMossbauereffectofYBa2Cu2.88Fe0.12O7-xsuperconductiveoxidefrom78to273K.TwominimaofrecoillessfractionandDebyetemperaturewerefoundnear110Kand220K.Itmeansthatlatticesofteninghappenednearthesetwotemperatures.Wealsoobservedminimaofisomershiftnear110Kandquadrupolesplittingincreasewhentemperatureislowerthan110K.Wesuggestthatlatticesofteningwouldleadtothedisplacementofoxygenatoms.Thismayberelativetosuperconductivetransition.

  • 标签: Y-Ba-Cu-Fe-O superconductor MOSSBAUER effect lattice softening
  • 简介:报道了国内外有关WC—M纳米涂层的原料制备、喷涂技术和涂层的显微结构及性能特点。其中包括nWC—Co纳米涂层的超音速喷涂、等离子喷涂、冷喷涂和多模式粉末结构等喷涂方法。综合了若干实验结果表明:与常规涂层相比nWC—Co涂层有更小的空隙度、更合理的组织结构和更高的韧塑性及更高的抗磨蚀能力。

  • 标签: WC—M WC—Co 纳米涂层 组织 性能
  • 简介:据报道,香港科技大学物理学系蒙民伟博士纳米科学讲座教授沈平的研究团队近日发现,于纳米结构下的石墨烯,其电子性能小至10μm仍可保持,此发现突破科学界纪录。

  • 标签: 电子性能 纳米结构 石墨烯 纳米科学 大学物理学
  • 简介:InvestigationhasbeencarriedouttofindtheeffectsofNdsubstitutionandCuadditiononthehydrogenstoragepropertiesofAB5-typealloywithamulticomponentLa0.6M0.4Ni4.8Mn0.2(M=Y,Nd)system.La0.6Y0.4Ni4.8Mn0.2,whichwasusedinanair-conditioningsystem,showedpoorhysteresisandslopingcharacteristics,whichledtoadecreaseconcerningthecoefficientofperformanceofthesystem.BythesubstitutionofNdforY,thehydrogenstoragecapacityincreased,andtheplateaupressuredecreasedalittle,butthehydrogenabsorptionkineticsdecreaseddramatically.CuadditioncaneffectivelyimprovethekineticsofhydrideformationwithoutchangingthehydrogenstoragecapacityofLa0.6Nd0.4Ni4.8Mn0.2.IthasbeenfoundthatLa0.6Nd0.4Ni4.8Mn0.2Cu0.1alloyshowedgoodhydrogenstoragecharacteristicsformetalhydrideair-conditioningsystem.Theresultsshowedthat,foreachcomponentofLa0.6Mo.4Ni4.8Mn0.2,theeffectivehydrogenstoragecapacityincreasedwithdecreaseoftheunitcellparameterc/aandthehydrogenabsorptionplateaupressureincreasedwithdecreaseoftheparametera.

  • 标签: 金属氢化物 空气调节系统 磁滞现象 动力学 储氢性能 La0.6M0.4Ni4.8Mn0.2
  • 简介:Thepresentstudyisconcernedwiththeeffectoffillermetalssuchasausteniticstainlesssteel,ferriticstainlesssteelandduplexstainlesssteelontensileandimpactpropertiesoftheferriticstainlesssteelconformingtoAISI409Mgrade.Rolledplatesof4mmthicknesswereusedasthebasematerialforpreparingsinglepassbuttweldedjoints.Tensileandimpactproperties,microhardness,microstructureandfracturesurfacemorphologyofthejointsfabricatedbyausteniticstainlesssteel,ferriticstainlesssteelandduplexstainlesssteelfillermetalswereevaluatedandtheresultswerereported.Fromthisinvestigation,itisfoundthatthejointsfabricatedbyduplexstainlesssteelfillermetalshowedhighertensilestrengthandhardnesscomparedtothejointsfabricatedbyausteniticandferriticstainlesssteelfillermetals.Jointsfabricatedbyausteniticstainlesssteelfillermetalexhibitedhigherductilityandimpacttoughnesscomparedwiththejointsfabricatedbyferriticstainlesssteelandduplexstainlesssteelfillermetals.

  • 标签: 铁素体不锈钢 冲击性能 电弧焊接 拉伸 奥氏体不锈钢 双相不锈钢
  • 简介:使用醋酸镍为前驱体通过一步法和成无毒的M3S2量子点.对M3S2量子点进行光致发光,XRD和透射电镜的分析表征结果表明:硫化镍在365nm的激发波长下的最大发射波长在469nm,量子点的平均粒径介于5-11nm之间.

  • 标签: 量子点 环境友好
  • 简介:TheeffectoftitaniumadditiononthemicrostructureandmechanicalpropertiesofbrassCu40Znhasbeenstudiedviathepowdermetallurgy(P/M)route.Thewater-atomizedCu40Zn—1.0wt%Tialloypowderwasconsolidatedatdifferenttemperaturesintherangeof400—600℃usingsparkplasmasintering(SPS)andhotextrusionsubsequently.Resultsshowthatthesuper-saturatedsolidsolutiontitaniumelementinrapidlycooledbrassCu40Znpowdercreatedhighchemicalpotentialforaprecipitatereaction,showingsignificantgrainrefinementeffectsontheconsolidatedCu40Znmatrix.Consequently,excellentmechanicalpropertieswereobtainedbyprecipitationhardeningandworkhardeningaftersinteringandextrusion,withyieldstrengthof390MPa,ultimatetensilestrengthof617MPa,andVickersmicro-hardnessof192HV,whichare28.7%,23.4%,and23.9%highervaluesthanthoseofextrudedCu40Znbrass,respectively.

  • 标签: 放电等离子烧结 黄铜合金 微观结构 力学性能 热挤压 析出行为
  • 简介:Inpursuingexcellentsupercapacitorelectrodes,wedesignedaseriesofM0S2/C0S2compositesconsistingofflower-likedMoS2andoctahedron-shapedCoS2throughafacileone-stephydrothermalmethodandinvestigatedtheelectrochemicalperformanceofthesampleswithvarioushydrothermaltime.Duetothecouplingoftwometalspeciesandabigamountofwell-developedCoS2andMoS2,theresultsindicatedthattheMoS2/CoS2compositeselectrodesexhibitedthebestelectrochemicalperfor-mancewithalargespecificcapacitanceof490F/gat2mV/sor400F/gat10A/gamongallsamplesasthehydrothermaltimereached48h(MCS48).Furthermore,theretentionofMCS48is93.1%after10000cyclesat10A/g,whichmanifeststheexcellentcyclingstability.TheoutstandingelectrochemicalperformanceofMCS48indicatesthatitcouldbeaverypromisingandnovelenergystoragematerialforsupercapacitorsinthefuture.

  • 标签: MoS2/CoS2 COMPOSITES HYDROTHERMAL time ELECTROCHEMICAL properties