简介：ＬａｓｅｒＴｒｅａｔｍｅｎｔｏｆＯｘｉｄｅＤｉｓｐｅｒｓｉｏｎＳｔｒｅｎｇｔｈｅｎｅｄＡｌｌｏｙｓＳｈａＷｅｉ（沙维）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｉｅｒｉａｌｓＳｃｉｃｎｃｅａｎｄＭｅｔａｌｌｕｒｇｙ，ＵｎｉｖｅｒｓｉｔｙｏｆＣａｍｂｒｉｄｇｅ，Ｕ...

简介：ＩｎｔｒｏｄｕｃｔｉｏｎＩＭＩ８２９ｔｉｔａｎｉｕｍａｌｏｙｉｓａｋｉｎｄｏｆｈｉｇｈｔｅｍｐｅｒａｔｕｒｅｎｅａｒαａｌｏｙ．Ｉｔｓｓｅｒｖｉｃｅｔｅｍｐｅｒａｔｕｒｅｉｓｕｐｔｏ５８０℃．ＩｔｈａｓｂｅｅｎｕｓｅｄｉｎＲＢ２１１５２５Ｅ４ｅｎ...

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简介：MoleculardynamicssimulationwascarriedouttoinvestigatetheliquidandamorphousmicrostructuresofbinaryAgx-Rh(100-x)(x=25,50,75inatomfraction)alloys.SegregationfeatureofhomogeneousinteratomicbindingofAg-Rhliquidwasfoundandprobed,whichcanberetainedintoamorphoussolidsuponrapidcooling.Homogeneousbindingmayoccurwhenthedifferenceintheelementalatomicsizesislessthan10%.Theicosahedrainliquidbeforetheformationofamorphousstateexistinastablestateandthenetworkformedby1551-clustersinmoltenalloyswouldinhibitthecrystallizationanddiffusionofatoms.Ahigherdegreeof1551-clusterswillbefavorabletoformmetallicglasses.

简介：X－raydiffraction(XRD)anddifferentialscanningcalorimetry(DSC)wereemployedtoinvestigatetheinfluenceofNicontentonthecrystallizationofamorphousZr70Cu30-xNix(atomfrationin%)alloys,ExperimentalresultsshowthatwiththeNicontentincreasingtheactivationenergiesforcrystallizationofamorphousZr70Cu30-xNixalloysincreasecorrespondingly,indicatingthatthethermalstabilityisgreatlyimproved.AlltheDSCtracesofamorphousZr70Cu30-xNixalloysexhibittwoexothermicpeaks,suggestingthatthecrystallizationprocessviaadouble-stageticles,whilethesecondonecorrespondstotheprecipitaionofnano-scaleZr2Niphaseandcrystallizationofresidualamporphousphase,ThemechanismonthecrystallizationofamorphousZr70Cu30-xNixalloyswasdiscussed.

简介：GaxIn1-xAs1-ySbyalloyshavebeengrownbyatmosphericpressureMOCVDonn-GaSb（Te-doped）substrate.Thesohdcompositionwasdeterminedbyusingelectronmicroprobe.ThealloysofGalnAsSbwithcompositioninmiscibilitygapweresuccessfullygrown.TheopticalpropertiesofGaxIn1-xAs1-ySbylaverswerecharacterizedbythephotoluminescenceandtheinfraredabsorption.Thespectralresponsesofp+-GaInAsSb/p-GaxIn1-xAs1-ySby/n-GaSbdetectorsshowedwavelengthcutoffat2.4μmanddetectivity-D*=5×108cmHz1/2/Watroomtemperature.

简介：ThehydrogenstoragepropertiesofTi1.2Fe+xCa(x=1%,3%and5%inmassfraction)alloyswasinvestigated.ResultsshowthatthemodifiedalloyscanbeactivatedwithoutanythermaltreatmentatroomtemperatureduetotheadditionofCaandexcessTiinthealloys.HydrogenstoragepropertiesofthesemodifiedalloysvarywithCaamountandreactiontemperature.Inaddition,theinfluencemechanismoftheadditionofCaandexcessiveTiontheactivationbehaviorandhydrogenstoragecapacityofthealloyswasdiscussed.

简介：MicrostructureandtextureofTi-Nb-Sibasedalloys,preparedbywaterquenchingfromβ-phasefield,coldrollingandrecrystallizationheattreatmentfollowedbywaterquenching,wereinvestigatedintermsofopticalmicrostructureandanalysisofX-raypolefigureresult.Inas-quenchedsample,relativelyrandomdistributionofpolefigurewasdetectedwithoutshowingaspecifictexturecomponent.Inas-coldrolledsample,however,itisfoundwell-developedseveraltexturecomponentsconsistingofrotatedcube,α-fiberandγ-fibertexturecomponentswhicharefrequentlyobservedinbcc-structuredmetalsandalloyswerefound.Therefore,texturecomponentsdevelopedinthepresentalloysarecloselyrelatedtothedeformationofβ-phaseeventhoughsmallamountofα″phaseco-existinthemicrostructure.Inrecrystallizedsample,α-fibertexturecomponentisweaklydetectedwhiletheothertexturecomponents,rotatedcubeandγ-fibercomponents,appearstoberelativelyunchanged.Noadditionaltexturecomponentsweredetectedbesidesthosetexturecomponentsobservedinthecoldrolledsamples.

简介：Reerystallizafionofcold-roUeddiscontinuousprecipitationmicrostructurewhichhasfinelaminarstructureinanAl-40%7m(atomfraction)binaryalloyisinvestigatedbyopticalmicroscopy,SEMandTEM.Itisfoundthattherearetwokindsofrecrystallizationmechanisms:continuouscoarsening(CC)anddiscontinuouscoarsening(DC).Thelattercanbedividedintocoarseningmainlydrivenbystoreddeformationenergyatcolonyboundariesandslipbandsandtheonemainlydrivenbyboundaryenergyintheareawithlittledeformation.ItisshownthattheadditionofCucanretardthenucleationofcoarseningcellsandtheirgrowth.X-RaydiffractionanalysisindicatedthemetastablephaseCuZn4transformedintoequilibriumphaseAl4Cu3Znduringtheheatingprocess.

简介：作为La-Mg-Y系统的一个例子，方法怎么建立单个阶段的热力学的模型在热力学的优化的过程被介绍。答案阶段(液体，以身体为中心立方，以脸为中心立方、包装hexagonalclose、双六角形拥挤不堪)与Redlich-Kister方程被建模。Thecompound精力模型被用来在La-Mg-Y系统描述金属间化合的混合物的热力学的函数。在La-Mg-Y系统的混合物Mg_2Y，Mg_(24)Y_5，Mg_(12)La，Mg_(17)La_2，Mg_(41)La_5，Mg_3La和Mg_2La被当作公式(Mg，Y)_2(La，Mg，Y)，Mg_(24)(La，Mg，Y)_4Y，Mg_(12)(La，Y)，Mg_(17)(La，Y)_2，Mg_(41)(La，Y)_5，Mg_3(La，Mg，Y)并且Mg_2(La，Y)分别地。一个模型(La，Mg，Y)_(0.5)(La，Mg，Y)_(0.5)被使用由MgLa和MgY描述复合MgMformed以便在La-Mg-Y系统与CsCl类型结构(B2)应付在body-centeredcubic答案(A2)和MgM之间的顺序混乱转变。单个阶段的吉布斯精力在La-Mg被优化，躺并且由CALPHAD的La-Mg-Y系统技术。液体的Theprojection我们为La-Mg-Y系统的表面被预言。包括Mg，艾尔，Cu，Ni，Mn，Zn和稀土元素形成的36二进制代码和15三元系统的基于Mg的合金数据库元素在SGTE被安装标准。

简介：X-raydiffraction(XRD)anddifferentialscanningcalorimetry(DSC)wereusedtoinvestigatethecrystallizationprocessofamorphousAl90TMxCe10-x(atomfractionin%;TM=FeorNi;x=3,5)alloys.AgingeffectswereexaminedbyX-raydiffraction.ThestructurecorrespondingtotheprepeakfortheamorphousAl90Fe5Ce5alloyismorestablethantheamorphousmatrix,butitisnotstableforamorphousAl90Ni5Ce5alloyduringthefirstcrystallizationstageandevendecomposesatroomtemperature.AlthoughbothAl-NiandAl-Fehavestrongchemicalbonding,thecrystallizationonsettemperatureofamorphousAl-Fe-CealloysismuchhigherthanthatofamorphousAl-Ni-Cealloys,whichislikelycausedbythedifferentstabilityofthestructurecorrespondingtotheprepeak.ThecrystallizationonsettemperatureincreasesasCe/NiratioincreasesinamorphousAl90NixCe10-xalloys,whereasitdecreasesasCe/FeratioincreasesinamorphousAl90FexCe10-xalloys.AbetteratomicpackingproducesasCecontentincreasesbecauseofthesizemismatchinAlNi-CesystemsandasFecontentincreasesbecauseoftheincreasingFecentralstructuralunits.

简介：当一个中等稳定的阶段在内部反应期间外面被猛抛时，在散开地区以内的渗透的原子的行为能基于热力学的考虑被解释。在Ni-Cr合金at1125℃的内部nitridation期间向降水前面通过矩阵为“登高”证实渗透的种类的散开，6000块N_2压力被预言。氮的如此的行为对在瓦格纳的边界条件相反“对内部反应的s描述。与降水反应联系的一个体积变化导致了在合金表面和internalnitridation前面之间的一个压力坡度。应力消除主要由镍的运输发生了到气体/金属的接口。管子控制散开creep在nitriding期间是主导的压力住所机制冲淡在在流动NH_3+H_2煤气的混合物下面的700℃的Ni-Cr合金。

简介：ＰａｓｓｉｖａｔｉｏｎｏｆＩｎｓｏｌｕｂｌｅＡｎｏｄｅｆｒｏｍＴｉ－ｂａｓｅＡｌｌｏｙｓｉｎＰｒｅｐａｒａｔｉｏｎｏｆＥｌｅｃｔｒｏｌｙｔｉｃＭｎＯ＿２ＹｕＺｈｅｎｇａｎｄＹａｎｇＳｈｅｎｇｓｈｕ（俞征）（杨生恕）ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓ...

简介：ＣｕｒｉｅＴｅｍｐｅｒａｔｕｒｅｏｆＡｍｏｒｐｈｏｕｓＦｅＳｉＢａｎｄＦｅＷＳｉＢＡｌｏｙｓＷａｎｇＬｉｎｇｌｉｎｇ，ＺｈａｏＬｉｈｕａ，ＨｕＷａｎｇｙｕ（王玲玲）（赵立华）（胡望宇））ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，ＨｕｎａｎＵｎ...

简介：Nuggetsplashduringaluminumalloysspotweldinghasadetrimentaleffectonweldnuggetintegrity,strengthanddurabilityoftheweldedjoints.Thisinvestigationisperformedtoidentifynuggetsplashfromvoltagesignalsbecausetheseareeasilyaccessibleon-line.Inthepresentwork,weproposeanovelmethodbasedonthewaveletpackettransformanditsenergyspectrumforpatternrecognitionofsplashsignal.Theresultdemonstratesthatthisnovelmethodismoreaccuracyandausefulwayofmonitoringthespotweldingquality.

简介：SolderingofLD31aluminumalloysusingSn-PbsolderpasteafterelectricbrushplatingNiandCucoatingswasnvestigated.ThetechnologyofelectricbrushplatingNiandCuwasstudiedandplatingsolutionwasdeveloped.Themicrostructureofthecoatings,solderedjointandfracturefacewereanalyzedusingopticmicroscopy,SEMandEDX.Theshearstrengthofsolderedjointcouldreachashighas26.83MPa.Theresultsshowedthatreliablesolderedjointcouldbeobtainedat230℃,theadhesionofcoatingsandLD31aluminumalloysubstratewashighenoughtobearthethermalprocessinthesoldering.

简介：Theeffectsoflow-CoAB5typehydrogenstoragealloyspreparedbyquenchingandannealingontheperformancesofMH-Nibatterieswereinvestigated,andthecharacteristicsofthelow-CoAB5typehydrogenstoragealloyswerecomparedwiththoseofthehigh-CoAB5typehydrogenstoragealloyaswell.Theresultsshowedthatthefasterthecoolingofthelow-Cohydrogenstoragealloyis,thebetterhomogeneityofthechemicalcompositionforthealloyandthelongercyclelifeofthebatteryare,buttheelectrochemicaldischargecapacityandhigh-ratedischargeabilityarereduced.Thehigh-ratedischargeabilityandchargeretentionofMH-Nibatteriesfortheconventionalas-castannealedlow-Cohydrogenstoragealloyweresuperiortothosefortherapidlyquenchedlow-Cohydrogenstoragealloyandthehigh-Cohydrogenstoragealloy,butalittleinferiorinthecyclelife.

简介：在二种铝锂alloys2090和2090+Ce的脱臼的微观结构借助于TEM技术被观察。到力量的8''和T_1precipitates的贡献被使用量的金属组织学的结果和微变丑的行为的分析独立计算；三角洲的共同加强的效果“andT_1猛抛被学习。结果证明三角洲共同加强的增加的关系“并且T_1根据1.4以近的山峰条件形成的q=，即，三角洲tau_p~(1.4)=三角洲字形物_(三角洲“)~(1.4)+三角洲字形物_(T_1)~(1.4)；但是增加的关系是近似一种线性关系(q=1)以未成年的条件并且成为抛物线形式什么时候over-aged(q=2)。共同加强的增加的关系三角洲的贡献“并且显然依赖于老化时间的T_1is。

简介：InordertoimprovetheelectrochemicalcyclestabilityofLa-Mg-Nisystem(PuNi3-type)hydrogenstoragealloy,NiinthealloyswaspartiallysubstitutedbyM(M=Cu,Al,Mn).AnewLa-Mg-NisystemelectrodealloysLa0.7Mg0.3Ni2.55-xCo0.45Mx(M=Cu,Al,Mn;x=0,0.1)werepreparedbycastingandrapidquenching.Theeffectsofelementsubstitutionandrapidquenchingonthemicrostructuresandelectrochemicalperformancesofthealloyswereinvestigated.TheresultsbyXRD,SEMandTEMshowthatthealloyshaveamultiphasestructure,includingthe(La,Mg)Ni3phase,theLaNi5phaseandtheLaNi2phase.Therapidquenchingandelementsubstitutionhaveanimperceptibleinfluenceonthephasecompositionsofthealloys,butbothchangethephaseabundanceofthealloys.Therapidquenchingsignificantlyimprovesthecompositionhomogeneityofthealloysandmarkedlydecreasesthegrainsizeofthealloys.TheCusubstitutionpromotestheformationofanamorphousphaseintheas-quenchedalloy,andareversalresultbytheAlsubstitution.Theelectrochemicalmeasurementindicatesthattheelementsubstitutiondecreasesthedischargecapacityofthealloys,whereasitobviouslyimprovesthecyclestabilityofthealloys.ThepositiveinfluenceofelementsubstitutiononthecyclelifeofthealloysisinsequenceAl＞Cu＞Mn,andnegativeinfluenceonthedischargecapacityisinsequenceAl＞Mn＞Cu.Therapidquenchingsignificantlyenhancesthecyclestabilityofthealloys,butitleadstoadifferentextentdecreaseofthedischargecapacityofthealloys.

简介：ThestructureandelectrochemicalpropertiesofanewlowcobalthydrogenstorageelectrodealloysLa1-xLixNi3.2Co0.3Al0.3(0≤x≤0.2)wereinvestigatedwithadifferentadditionsofLiinreplacementofLa.WiththeincreaseofLicontentsthemaximumdischargecapacityincreasesfrom240mAh·g-1(x=0)to328.4mAh·g-1(x=0.1)andthecyclestabilityisimprovedcorrespondingly.ThecapacitydecaycanremaiN28.6%(x=0.2)after230charge/dischargecycles.Thehighratedischarge(HRD)abilityofthealloys(x≤0.1)isimprovedandthebestHRDis34.1%(x=0.1)underthedischargecurrentdensity1200mA·g-1.ItisfoundthatthepreparedalloysarebasicallycomposedofLaNi5asmatrixphaseandLaNi3assecondphase(x≤0.1).ButtheabundanceofLaNi3phasedramaticallydecreaseswithincreasingx.Whenx=0.2,anewphaseAl(NiCo)3isformed.