简介：基于蠕变模型采用有限元法对WLCSP30器件Sn3.9Ag0.6Cu焊点可靠性及疲劳寿命进行预测.研究发现WLCSP器件整体的最大应力集中在阵列最拐角焊点的上表面处,该部位可能成为焊点裂纹的发源地,试验结果也验证了模拟结果的正确性.对焊点应力—应变分析,发现焊点部位出现明显的蠕变应变和蠕变应变能累积现象,结合焊点疲劳寿命方程,预测焊点疲劳寿命,发现基于蠕变应变能密度的计算结果和试验结果较吻合,但是基于蠕变应变的预测结果和试验结果相差较大,因此基于蠕变应变的疲劳寿命预测方程需要进一步的研究.

简介：IntroductionTungsten-copperalloypowdersareusedinmanyfieldsonaccountofthehighelectricandthermalconductivitiesofcopperandhighmeltingpointoftungsten.W-Cupowders,aspreparedconventionallybymeansofinfiltration,hasthedisadvantageofinhomogeneityinmicrostructure,andaredifficulttoworkwithaftersintering.

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.

简介：以氯化钡、氯化锶和四氯化钛为原料，在190℃下反应10h合成了平均粒径为80nm左右的立方相Ba0.6Sr0.4TiO3粉体。粉体粒度均一，团聚少，纯度高，杂质离子少。用X射线衍射（XRD）、扫描电子显微镜（SEM）、X射线荧光光谱议（XRF）等分析方法对合成粉体的物相、形貌和组成进行了表征，并研究了初始配比、矿化剂KOH过量浓度、水热时间和温度等条件对合成Ba0.6Sr0.4TiO3粉体的影响。

简介：MechanicallyactivatedW-Cupowdersweresinteredbyasparkplasmasinteringsystem(SPS)inordertodevelopanewprocessandimprovethepropertiesofthealloy.Propertiessuchasdensityandhardnessweremeasured.ThemicrostructuresofthesinteredW-CualloysampleswereobservedbySEM(scanningelectronmicroscope).Theresultsshowthatsparkplasmasinteringcanobviouslylowerthesinteringtemperatureandincreasethedensityofthealloy.Thisprocesscanalsoimprovethehardnessofthealloy.SPSisaneffectivemethodtoobtainW-Cupowderswithhighdensityandsuperiorphysicalproperties.

简介：Inordertotransfertheheatfromthearmortothecoolant,tungstenhastobeconnectedwithacopperheatsink.Thejointtechnologyisthemostcriticalissueformanufacturingplasmafacingcomponents.Consequently,thereliabilityofthejointsshouldbeverifiedbyagreatnumberofhigh-heat-flux（HHF）teststosimulatetherealloadconditions.W/CubrazedjointtechnologywithsliverfreefillermetalCuMnNihasbeendevelopedatSouthwesternInstituteofPhysics（SWIP）.Screeningandthermalfatiguetestsofonesmall-scaleflattileW/CuCrZrmockupwereperformedona60kWelectron-beamMaterialtestingscenario（EMS-60）constructedrecentlyatSWIP.Themodulesuccessfullysurvivedscreeningtestwiththeabsorbedpowerdensity(Pabs)of2MW/m2to10MW/m2andthefollowing1000cyclesatPabsof7.2MW/m2withouthotspotsandoverheatingzonesduringthewholetestcampaign.MetallurgyandSEMobservationsdidnotfindanycracksatbothsidesandtheinterface,indicatingagoodbondingofWandCuCrZralloy.Inaddition,finiteelementsimulationsbyANSYS12.0underexperimentalloadconditionswereperformedandcomparedwithexperimentalresults.

简介：对Cu-W-Ni-C与Ag-ZnO10触头材料的性能进行了对比和研究.在相对密度相同时,CuW-Ni-C材料的电阻率与Ag-ZnO10材料的电阻率接近,而硬度高于Ag-ZnO10材料的硬度.温升和通断能力试验结果表明:Cu-W-Ni-C材料在电力机车电器上完全可替代Ag-ZnO10材料.

简介：Inthisstudy,tungsten(W)wascoatedonacopper(Cu)substratebyusingdouble-glowdischargetechniqueusingapureWpanelasthetargetandargon(Ar)asthedischargeandsputteringgas.ThecrystalstructureoftheWcoatingwasexaminedbyX-raydiffraction(XRD).Scanningelectronmicroscopy(SEM)wasperformedwithcross-sectionimagestoinvestigatethepenetrationdepthofWintotheCubody.Additionally,thepropertiesofwearabilityresistance,corrosionresistanceandmechanicalstrengthoftheWcoatedCumatrixwerealsomeasured.Itisconcludedthatindouble-glowplasma,WcoatedCucanbefacilelyprepared.ItisnoticedthatthetreatmenttemperatureheavilydominatesthepropertiesoftheW-Cucomposite.

简介：这研究的目的是为Cu-0.6Cr在团结过程预言形态学(集体部分，%)由真空的合金连续的扔(VCC)并且由观察试验性的结果验证它的精确性。在数字模拟，方面，有限差别(FD)方法和修改细胞的自动机(MCA)模型被用来从实际扔的操作用真实数据模仿宏温度地，微集中的地，成核和Cu-0.6Cr合金的谷物生长。从观察扔的实验，初步的谷物形态学是由VCC过程的方向性的圆柱的谷物。由MCAFD模型的团结形态学与实际扔的实验的结果一致很好。

简介：W-25Cualloysweremicrowavesinteredina2.45GHzmultimodeapplicator.Thedensification,microstructureandtheirdependenceonsinteringmodeandFeadditionwereinvestigatedindetail.Owingtothevolumetricheatingintrinsicinmicrowaveprocessing,amicrostructurewithlargerWgrainsizeincenterregionswasobservedasagainstlargergrainsizeinedgeregionsforconventionalsintering.Microwavesinteringdemonstratesitsintrinsicadvantagessuchasrapidheatingrate,densificationenhancementandmicrostructuralhomogeneity;butitundesirablypromotesWgraingrowth.Undermicrowavesintering,theroleofFeadditiononcompactconsolidationisnotsosubstantialasunderconventionalsintering.MoreoverFedegradesthemicrostructuralquality,generatingworseuniformityandcoarserWgrains.

简介：W-Cu梯度功能材料的高W含量侧具有低热膨胀率、高强度和耐热流冲蚀等特点,高Cu含量的另一侧具有高导热性能,而中间过渡层可使内部热应力获得良好的缓和;该材料作为热沉材料、面向等离子体材料以及触头材料等的应用具有非常大的发展潜力,其研究受到广泛的重视。本文作者对W-Cu梯度材料的研究进展进行综合评述,介绍了W-Cu梯度功能材料的设计、制备及评价方法;根据其工作环境,着重对W-Cu梯度功能材料的致密性,热膨胀,热导率,热损蚀和热冲击等性能进行评价,并对W-Cu梯度功能材料的进一步发展作了展望。

简介：爬Zr-1.5Nb-0.4Sn-0.1Fe-0.1Cu合金表的行为从50MPa在压力范围从300掳C被调查到400掳C到180MPa沿着滚动方向。测量紧张率从8.8脳10?10s?1～4.7脳10?7s?1。激活精力被估计在这合金估计creep变丑机制。紧张率是稍微在低应力的dierent，当它在高压力显示出不同dierence时。有增加的这合金增加的压力代表使用了根本测试温度的应力。Zr-1.5Nb-0.4Sn-0.1Fe-0.1Cu合金的creep变丑被diusion控制，这被结束在低压力区域并且由在高应力爬脱臼爬区域。

简介：采用铸锭冶金以及形变热处理工艺，制备了不同Cu，Mg含量的Al-xCu—yMg-0．6Ag合金。通过拉伸性能测试、差热分析（DSC）以及扫描电镜（SEM）与透射电镜（TEM）分析，研究Cu，Mg含量对合金组织与力学性能的影响。结果显示：增加Cu与Mg的含量，能提高基体合金的时效硬化效果与抗拉强度。185℃峰时效时，Al-xCu—yMg-0．6Ag合金的主要强化相由片状Ω相和少量θ’相组成。随着Cu含量的增加，峰时效态合金中Ω相体积分数增大。增加Mg的含量，能加速合金的时效硬化过程，减小Ω相的尺寸。

简介：Aseriesoftitlecompoundsaswellastheirprecursorsweresynthesizedbyprecursorroute.TheirPXRDpatternswerecharacterizedwithZrW2O8orZrMo2O8modelbyRietveldmethod.Thethermalcontractionsofthecompoundsweredeterminedaccordingtothevariable-temperaturePXRDdataandNTEcoefficientswerepresented.Thetwo-phasemixtureofZrW0.4Mo1.6O8wasalsoanalyzedindividually.

简介：用改进的溶胶一凝胶法制备光滑致密的预晶化铈（Ce）和锰（Mn）共掺钛酸锶钡（CeMn—SST）薄膜。电容－电压曲线表明，随着薄膜厚度的增加，综合介电性能大幅度改善，8层薄膜显示介电常数约为1300、低于0．007介电损耗、高于58％调谐率及接近180优质因子等优化介电性能，为主要沿（1101晶面层状生长的钙钛矿结构。

简介：Adirectelectrolesscopper(Cu)coatingontungstenpowdersmethodrequiringnosurfacetreatmentorstabilizingagentandusingglyoxylicacid(C2H2O3)asareducingagentwasreported.TheeffectsofcoppersulfateconcentrationandthepHoftheplatingsolutiononthepropertiesofthepreparedW@Cucompositepowderswereassessed.ThecontentofCuinthecompositepowderswascontrolledbyadjustingtheconcentrationofcoppersulfateintheelectrolessplatingsolution.Auniform,dense,andconsistentCucoatingwasobtainedundertheestablishedoptimumconditions(flowrateofC2H2O3=5.01mL/min,solutionpH=12.25andreactiontemperature45.35℃)byusingcentralcompositedesignmethod.Inaddition,thecrystallineCucoatingwasevenlydispersedwithintheW@CucompositepowdersandCuelementinthecoatingexistedasCu0.TheformationmechanismfortheW@Cucompositepowdersbyelectrolessplatingintheabsenceofsurfacetreatmentandstabilizingagentwasalsoproposed.

简介：Withpricesformetalresourcessuchasnickelandmolybdenumsoaring,thereisaheightenedsenseofcrisisconcerningresourcescarcity.WhileType304,themostcommonstainlesssteel,offersexcellentcorrosionresistance,itspriceisaffectedsignificantlybythecostofnickelbecauseofits8%nickelcontent.ThestainlesssteelthathasthesamecorrosionresistanceasthatofType304anddoesnotcontainnickelandmolybdenumhasbeenrequired.JFESteelCorporationhasdevelopedanew21%Cr-0.4%Custainlesssteel,theworld’sfirstferriticstainlesssteel,whichoffersequivalentcorrosionresistancetoType304whilecontainingabsolutelynonickelormolybdenum,tworaremetals.Thenewlydevelopedsteelcontains21%chromiumwiththeadditionof0.4%copper.Thedevelopmentofthesteelisbasedonanewdiscoverythatthepassivefilmsofstainlesssteelscouldbestrengthenedbythesynergyeffectofhighchromiumcontentandcopperaddition.Copperadditionenrichesthechromiumcontentinpassivefilmsafterfieldexposure.Newlydeveloped21%Cr-0.4%CustainlesssteelisadoptedformanyapplicationsasasubstitutionforType304,includingcommercialkitchenware,buildingmaterialsandindustrialmachinery.ThesteelisexpectedtobeanewstandardofaferriticstainlesssteelasasubstitutionforType304.

简介：ThestructureandhydridingperformanceofLa0.6Nd0.4Ni4.8Mn0.2Cux(x=0～0.4)alloyswereinvestigatedinordertodevelopsuitablematerialsformetalhydrideairconditioner.TheeffectofCuadditiononthecrystalstructure,equilibriumpressure,hydrogencapacityandhysteresisaswellashydrogenabsorption/desorptionkineticsweresystematicallystudiedbyusingthemeasurementofP-Cisotherms,X-raydiffractionandscanningelectronmicroscopy.AstheamountofCuincreases,theplateaupressureincreasesandhydrogenabsorption/desorptionkineticsisimproved,buttheeffectivehydrogenstoragecapacitydecreases.Itisshownthatvariationsinthebasalplaneparameteracanbeusedasanindicationfortheplateaupressurechanges.Withtheincreaseofparametera,theplateaupressuredecreases.ForLa0.6Nd0.4Ni4.8Mn0.2Cux(x=0～0.4)alloysthereisarelationshipbetweentheeffectivehydrogenstoragecapacitiesandtheratiosoftheirunitcellparameterscanda.Theeffectivehydrogenstoragecapacitydecreaseswithincreaseofa/c.

简介：采用热机械合金化制备纳米晶W-Cu复合粉末。通过XRD、SEM、激光粒度测试等方法对球磨后的粉末进行表征。结果表明：随球磨时间延长,W的晶粒尺寸不断减小,球磨30h后W的平均晶粒尺寸为41nm左右;球磨初期,粉末迅速细化;随球磨时间延长,粉末粒度有所增加;进一步增加球磨时间,粉末粒度减小。球磨粉末还原后有较高的烧结活性,1200℃烧结后相对密度可达97%以上。烧结材料的组织非常均匀,且晶粒细小。

简介：采用喷雾干燥-氢气还原法制备出W-20wt%Cu超细复合粉末,并对由该复合粉末所制得的压坯进行了高温烧结,利用SEM、XRD等分析手段对复合粉末的特性和烧结体的组织进行了表征和观察。实验结果表明,由该方法制备的W-20wt%Cu超细复合粉末颗粒细小,平均粒径在200nm左右;喷雾干燥后的氧化物复合粉末在还原后产生了新的合金相（Cu0.4W0.6）,还原后的复合粉末由Cu0.4W0.6相和Cu相组成,而且两相的晶粒度达到纳米级,其中Cu0.4W0.6相的晶粒约为33nm,Cu相的晶粒约为63nm;复合粉末具有很高的烧结特性,经高温烧结后合金致密度达到98%以上,而且金相组织分布均匀。