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简介：Lowtemperaturecompositechromizingisaprocesscomposedofaplainion-carbonitridingorion-nitridingat550～580℃,followedbyalow-temperaturechromizinginasalt-bathof590℃.ThemicrostructureandpropertiesofthelowtemperaturecompositechromizedlayeronH13toolsteelwereinvestigatedusingmetallography,X-raydiffraction,microanalysis,hardnessandweartests.Itwasfoundthatthislowtemperatureprocesswasthermodynamicallyandkineticallypossible,andthecompositechromizedlayeronH13steel,withathicknessof3～6μm,consistedofthreesub-layers(bands),viz.theouterCr-richone,theintermediate(black)one,andtheinner,originalwhitelayer.Afterchromizing,theformerdiffusionlayerwasthickened.TheresultsofX-raydiffractionshowedthatthecompositechromizedlayercontainedsuchnitridesandcarbidesofchromiumasCrN,Cr2N,(Cr,Fe)23C6,and(Cr,Fe)7C3,aswellasplainα-(Fe,Cr).Ahighsurfacemicrohardnessof1450～1550HV0.025,whichismuchhigherthanthatobtainedbytheconventionalioncarbonitridingandionnitriding,wasobtained.Inaddition,anexcellentwearresistancewasgainedonthecompositechromizedlayer.

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简介：Thenon-isothermalcrystallizationkineticsofpolyamide6/diamine-modifiedmulti-walledcarbonnanotube(PA6/D-MWNT)nanocompositewasinvestigatedbydifferentialscanningcalorimetry(DSC).ThemodifiedAvramiequation,theOzawaequationandthecombinedAvrami/Ozawaequationwereemployedtoanalyzethenon-isothermalcrystallizationdata.ThecrystallizationactivationenergieswerealsoevaluatedbytheKissingermethod.ItwasfoundthatthecombinedAvrami/Ozawaequationcouldsuccessfullydescribethenon-isothermalcrystallizationprocess.TheresultsshowedthatD-MWNTsnotonlyactedaseffectivehetero-geneousnucleatingagentsforPA6andnoticeablyincreasedthecrystallizationtemperatureofPA6,butalsoinfluencedthemechanismofnucleationandcrystalgrowthofPA6andthenreducedtheoverallcrystallizationrateoftheneatPA6matrix.ThecrystallizationactivationenergyforthenanocompositesamplewasgreaterthanthatoftheneatPA6,whichindicatedthattheadditionofD-MWNTshinderedthemobilityofPA6chainsegments.

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简介：微观结构和Ni//3艾尔的机械性质基于拥有低杂质内容的Ni-Al-Mosuperalloy-IC6，由水花免职技术的高密度被学习了。结果显示IC6合金在空间和中间的温度两个都有好张力的力量和延伸。(编辑作者摘要)6个裁判员。

简介：据报道,国务院总理温家宝日前主持召开国务院常务会议,研究部署进一步发挥科技支撑作用、加快国家科技重大专项实施工作,讨论并原则通过《促进生物产业加快发展的若干政策》。

简介：Ionbeamenhanceddeposition(IBED)wasemployedtoincreasethefrettingfatigueresistanceofTi6AI4V.CrNandTiNhardcoatingswereappliedonthebasematerialandshotpeeningwascombinedwiththehardcoatingstostudytheduplexeffectonfrettingfatigueresistance,TheIBEDcoatingsexhibitedagoodbondingstrength.Theydidnotspalloffevenaftershotpeening.However,anoptimumcompositionofCrNshowedbetterfrettingfatigueresistancethanthatofTiNwiththesameprocessingparameters.

简介：La9.33Si6O26氧离子导体被稳固的州的reactionmethod.Its综合结构被单个水晶的X光检查衍射分析在结果显示出的roomtemperature.The决定那La9.33Si6O26氧化物让磷灰石组织，空间groupP6_3/m.AC阻抗大小显示了在氮的氧化物sintered在空中比那些sintered有高得多的电导率。传导性上的谷物边界的效果被讨论。

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简介：Becauseoftheexcellentmechanicalpropertiesof34C「NiMo6steel,itiswidelyusedinhigh-valuecomponents.Manyconventionalapproachestostrengthening-steelstypicallyinvolvethelossofusefulductility.Inthisstudy,34CrNiMo6Steelhavinghighstrengthandductilityisproducedbylasersolidforming(LSF)w让haquenching-tempering(QT)treatment.TemperingofbainiteismainlybysolidphasetransformationinthepreviousLSFlayersduringtheLSFprocess.ThestablemicrostructureofLSFconsistsofferriteandfinecarbides.Themicrostructuretransferstotemperedsorbiteafterheat-treatment.ThetensilepropertiesoftheLSFsteelmeetthoseofthewroughtstandard.TheUTSandelongationofLSFsampleat858MPa,19.2%,respectively,aregreaterthanthoseofthewrought.TheQTtreatmentenhancedtheultimatetensilestrengthandyieldstrengthoftheLSFsample.Theultimatetensilestrength,yieldstrength,reductioninarea,andelongationoftheLSF+QTsampleat980MPa,916MPa,58.9%,and13.9%,respectively,aregreaterthanthoseofthewroughtstandard.TheyieldstrengthoftheLSF+QTsampleisapproximately1.27timesthatofthewrought.TheLSFsamplesfailedinaductilefracturemode,whiletheLSF+QTsamplesshowedmixed-modefailure.ThedefectshaveonlyasmalleffectonthetensilepropertiesowingtotheexcellentductilityoftheLSFsample.

简介：据报道，受到日本地震影响，半导体硅晶圆供给缺口将逐渐在2011年6月份半导体业者库存见底之际，产生明显的缺料危机，再加上日本拟关闭核电厂，接下来的电力短缺恐将进一步影响上游硅晶圆的供料吃紧。据半导体业者表示，以往在每季底才开始谈下季半导体硅晶圆价格，今年在恐缺货、

简介：周廉男。1940年3月出生，吉林舒兰县人，中共党员。海内外著名的材料科学家与工程专家。1994年遴选为中国工程院首批院士。2004年被法国傅立叶大学授予名誉博士学位。

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简介：AnewcompoundK6Ti0.67Nb15.33O42waspreparedforthefirsttimebysolidstatereactioninK2O-Ni2O3-Nb2O5ternarysystem.Thenewcompoundwascharacterizedbyelectronprobe,X-raypowderdiffractionandDTA.TheresultofX-raypowderdiffractionshowsthatK6Ti0.67Nb15.33O42crystallizesthehexagonalsystemwithunitcellparametersa=9.1341(5)A,c=12.090(1)A.andspacegroupP62/mcm(193).

简介：采用单辊法制备了宽20mm、厚25μm的Fe78Si9B13合金带材，用绕带机将其绕制成环型磁芯，然后将磁芯进行退火处理，结果表明，随着退火温度的升高，Fe78Si9B13非晶磁芯的初始磁导率m、饱磁感应强度Bs和矫顽力Hc呈先增大后减小的趋势，当退火温度达到450℃时，磁化曲线呈现出一定的线性关系，即恒导磁特性。将经4500（=／100min退火的Fe78Si9B13非晶磁芯用环氧树脂进行封装后，环氧封装后μi和Bs减小，而Hc和损耗Ps增大，磁化曲线和损耗曲线的形状与封装前相同。

简介：双相不锈钢1Cr18Ni11Si4AlTi由前苏联研制，目前在我国某些特殊行业中有重要的作用。根据我国现有标准GJB2294—95和GB／T1220—92组织生产，发现按标准中现行成分设计、热处理制度生产的产品与标准要求的力学性能（屈服强度σ0．2）需达到的规定值存在较大差异，很难达到所需要的屈服强度。通过完善相关成分和工艺参数，获得了满意的金相组织和优良的综合力学性能。通过试验探讨了生产实际与标准中的部分规定存在的差距。

简介：世界领先的创新增值塑料解决方案供应商博禄公司今天宣布，将其新一期的乙烯裂解装置建造合同发包给由林德工程公司（LindeEngineering）。此裂解装置每年的生产能力将达到近150万吨，并将成为世界上最大的气体裂解装置。