简介:Al2O3-MgOcastableshavebeenwidelyusedforworkingliningsofsteelladleduetotheirsuperiorhotstrengthandcorrosionresistance.Inthiswork,effectsofmicrosilica,ultrafinealuminaandMgOfinesadditionsontherheologicalbehaviorofthecastableswereinvestigatedbymeansofIBBrheometerV1.0tomeasuretorque(shearstress)undervaryingshearrates.Theresultsshowthatrheologicalpropertiesofcastablesatvaryingshearratesaresignificantlyimprovedwithincreaseofmicrosilicaadditions(from1mass%to5mass%)andcorrespondingdecreaseinwateraddition;thereisonlylittlechangeinrheologicalbehaviorwithvariationofultrafinealuminaandMgOfinesadditions.Optimumultrafinealuminaandmicrosilicaadditionsarerecommendedforcastableswithgoodrheologicalbehavior.
简介:用粒度为63μm和14μm的SiC粉末为原料,在注射温度和注射压力分别为160℃和70MPa、粉末装载量(体积分数)为63%的条件下,获得SiCp注射坯,经过溶剂脱脂和真空热脱脂以及1100℃/7h的真空预烧结后,在1000℃、N2气氛下进行Al合金熔渗,制备高体积分数63%SiCp/Al复合材料电子封装壳体。研究表明,熔渗组织均匀、致密,SiC颗粒均匀分布在Al基体中。熔渗时需要严格控制熔渗时间,熔渗时间超过10min后会导致坯体被Al合金熔体过度熔渗,从而在复合材料表面产生Al合金层,时间越长,Al层厚度逐渐增加。最终制得的高体积分数63%SiCp/Al复合材料封装壳体的尺寸精度优于0.3%,其热物理性能优异,热膨胀系数和热导率分别为7.2×10-6K-1和180W/m·K,密度为3.00g/cm3,能够满足电子封装材料性能的要求。
简介:ArapidlysolidifiedAl-2.5Ti-2.5Fe-2.5Cr(massfractionin%)alloywaspreparedbymeltspinning.Asquenchedandas-annealedmicrostructureswerestudiedbyX-raydiffractometry(XRD),transmissionelectronmicroscopy(TEM),high-resolutiontransmissionelectronmicroscopy(HREM)andenergydispersivespectrum(EDS)analysis.Themicrohardnessofthealloyatdifferentannealingtemperatureswasmeasured.TheresultsobtainedindicatethatthemicrohardnessoftherapidlysolidifiedAl-2.5Ti-2.5Fe-2.5Cralloydoesnotvarywithdifferentannealingtemperatures.Theas-quenchedmicrostructureofthealloyincludestwokindsofdispersedprimaryphases:Al3TiandAl13(Cr,Fe)2.Afterannealingat400℃for10h,thestablephaseAl13Fe4appearsinthemicrostructure.
简介:Thecorrosionbehaviorandanti-corrosionmechanismoftheZn-Ni-Al2O3compositecoatingwereinvestigatedbySEM,EDSandXPS.TheresultsindicatethatthecorrosiontypeoftheZn-Ni-Al2O3coatingsinneutral5wt.%NaClsolutionisuniformcorrosion.ThepresenceofcompactanduniformlydispersednanoaluminaparticlessubstantiallyinhibitsthecorrosionofZn-Ni-Al2O3compositecoatings.Intheinitialcorrosionstage,thecorrosiveproductsofZn-NimatrixformacompactZnCl2·4Zn(OH)2layer.Withthedevelopmentofcorrosion,somenanoaluminaparticlesareembeddedandformaNienrichmentlayer.InNienrichmentlayer,NipresentsasNiandNiO.
简介:Theeffectsofconcurrentpulsesinholdingdurationonsuperplasticityof2091Al-Lialloyhavebeeninvestigatedinthispaper.Theresultsofsuperplasticdeformationshowedthatconcurrentpulsesinholdingdurationdecreasedtheoptimumholdingtimeforsuperplasticdeformation(ε=3.33×10-2s,T=500℃)from15to5minandincreasedelongation(δ)from530to550%.Themetallographicobservationsshowedthatthespecimensappliedlybyconcurrentpulsewerecom-pletelyrecrystallizedafterholding5minat500℃,andgrainsrefinedtoabout2μm,andthosespec-imensunappliedcurrentpulseswerepartlyrecrystallizedevenafterholding15minat500℃.theelectronprobeanalysesindicatedthatconcurrentpulsespromotedatomicdiffusion.Itispointedoutthatconcurrentpulsesaccelerateatomdiffusionanddislocationmotion.increasenucleationrateofrecrystallizationanddecreasetheoptimumholdingtimeforsuperplasticdeformationandincreasesuperplasticproperties.
简介:TheinfluencesoffourkindsofadditivesaddedintothematrixofMgO-Al2O3unbunedproductswereinvestigated,TheresultsshowthatsampleswithproperMgO/Al2O3rationandproperadditionofCr2O3(2%-4%)havegoodthermalshockresistanceandslagcorrosionresistanceaswell,XRDandSEMdeterminationresultsindicatethatakindofcompoundspinel(Mg,Al,Cr)O4wasformedandthemicrostuctureofthesamplesaredenser.
简介:SiCp/Al是颗粒增强铝基复合材料中研究较多、应用较广泛的一种.文中综述了SiCp/Al复合材料的制备方法,并简述了今后的研究方向.
简介:以便得到TiB2-Al2O3的同质的混合物和协议,一个表面修正方法被用来准备nano规模的杂交Al2O3涂的TiB2粒子。PE蜡粒子是第一到由杂交,然后nano规模Al2O3粒子的TiB2粒子上涂又是涂的到由PE蜡粒子涂的TiB2的表面上。SEM,TEM和版本被用来描绘同样收到的核心/壳粒子和它的协议的微观结构。试验性的结果显示出那粒子规模TiB2和Al2O3的同质的分散能不仅在混合粉末而且在使脱蜡的协议被形成。协议当时是由煤气压的sintering(GPS)的sintered。物件顶端的装饰物产品显示出与参考样品由正常方法制作了作比较的改进技工性质。
简介:PhasesandmicrostructuresofthreehighZncontainingAl–Zn–Mg–Cualloyswereinvestigatedbymeansofthermodynamiccalculationmethod,opticamicroscopy(OM),scanningelectronmicroscopy(SEM)energydispersivespectroscopy(EDS),X-raydiffraction(XRD),anddifferentialscanningcalorimetry(DSC)analysis.TheresultsindicatethatsimilardendriticnetworkmorphologiesarefoundinthesethreeAl–Zn–Mg–Cualloys.Theas-cast7056aluminumalloyconsistsofaluminumsolidsolution,coarseAl/Mg(Cu,Zn,Al)2eutecticphases,andfineintermetalliccompoundsg(MgZn2).Bothofas-cast7095and7136aluminumalloysinvolvea(Al)eutecticAl/Mg(Cu,Zn,Al)2,intermetallicg(MgZn2),andh(Al2Cu).Duringhomogenizationat450°C,fineg(MgZn2)candissolveintomatrixabsolutely.Afterhomogenizationat450°Cfor24h,Mg(Cu,Zn,Al)2phasein7136alloytransformsintoS(Al2CuMg)whilenochangeisfoundin7056and7095alloys.ThethermodynamiccalculationcanbeusedtopredictthephasesinhighZncontainingAl–Zn–Mg–Cualloys.
简介:Inthepresentstudy,sampleswereextensivelycollectedthroughoutthestainlesssteelmanufacturingprocess.Thethree-dimensionalmorphologyofinclusionswasrevealedbynon-aqueoussolutionelectrolysis.Thehighconcentrationofaluminuminferrosiliconcausedtheincrementof[Al]sinsteelandAl2O3ininclusions,whichledtothehighermeltingtemperatureofinclusions.ItwasconcludedthattheapplicationoflowAlferrosiliconandcalciumtreatmentcouldpreventtheformationofAl2O3-richinclusions.
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简介:Fe-Ni-Almixturesashot-pressingsinteringadditivetoTitaniumdiboride(TiB2)werestudied.ItisfoundthatliquidalloyformedunderhightemperaturehardlyhaseffectsonthedensificationbehaviorsofTiB2-independent.Fe-Ni-AladditivejustworksasfillerbetweenTiB2particlesanddoesnotchangetheTiB2-independentsinteringbehaviors.PressingmodehasagreateffectontheliquidflowingbetweenTiB2particles.Multiple-stepspressingmodewillgivemoretimeandspacefortheliquidflowingandimprovetherelativedensityofTiB2-Fe-Ni-Alcermet.
简介:透明的传导性的铝做了锌氧化物(ZnO:艾尔,偶氮)电影被rf(收音机频率)在玻璃底层上准备磁控管从ZnO劈啪作响:3wt%艾尔2O3陶器的目标。氩气体压力的效果(PAr)与小变化被调查在这些电影的电、光、结构的性质上理解影响。使用X光检查衍射(XRD)并且扫描电子显微镜学(SEM)的结构的考试证明ZnO:薄电影是的艾尔(002)面向。抵抗力价值被四点的探查与5.76穩摥甠楳杮愠?灯楴業敺?票牤瑯敨浲污洠瑥潨?倠牵?桰獡?景?㈱?眠獡朠瑯愠?的最低抵抗力测量?潣灭牡瑡癩汥?潬敷?整灭牥瑡牵?挨愮??‰??楳瑳?景漠敮?睴?琠牨敥?牯映畯?慬敹獲漠?敭慴?晲捡獥瀠慬散?湩琠敨渠慥?楦汥?敲楧湯漠??業牣獯牴灩瀠瑡档愠瑮湥慮?桔?湡整湮?慲潤敭猠獹整?慧湩椠?浩牰癯摥戠????潣灭牡摥琠?桴?慰'?湡整湮?污湯?愠摮琠敨爠摡慩楴湯瀠瑡整湲栠污?吗潰敷?敢浡楷瑤?獩爠摥'转棳_??L潳灲楴湯瀠慥獫眠牥?獡楳湧?敧愠敲?吠敨栠杩汨?晥楦楣湥?L潳灲楴湯漠?
简介:利用平衡合金法,采用扫描电镜-能谱仪和X射线衍射方法对Al-Fe-Sn三元系973和593K等温截面的相关系进行实验测定。实验结果表明:在此两个截面上均未检测到三元化合物;973K时液相中Fe的最大固溶度为1.6%(摩尔分数),而593K时Fe和Al在液相中的最大固溶度分别为0.6%和5.1%(摩尔分数);在973和593K等温截面上,Sn在Fe-Al化合物中的最大固溶度分别为4.2%和2.3%(摩尔分数);Fe-Al化合物均能与液相保持平衡。
简介:AnewmethodforcorrosionprotectionofAl-basedmetalmatrixcomposites(MMC)wasdevelopedusingtwo-stepprocess,whichinvolvesanodizinginH2SO4solutionandsealinginrareearthsolution.Corrosionresistanceofthetreatedsurfacewasevaluatedwithpolarizationcurves.TheresultsshowedthattheeffectoftheprotectionusingrareearthsealingisequivalenttothatusingchromatesealingforAl6061/SiCp.TherareearthmetalsaltcanbeanalternativetothetoxicchromateforsealinganodizedAlMMC.
简介:TiN-Al2O3compositepowderswithdifferentTiNcontents(0,10vol%,20vol%,30vol%and40vol%)werepreparedwithmicrometerTiNandα-Al2O3powder(theirpuritieswere99%)asstartingmaterialsbywetballmillingfor5h.TiN-Al2O3compositewerethenpreparedbypressingtheabovecompositepowders,dryingat200℃for12handfiringat1800℃for3hinnitrogenatmosphereinhot-pressingfurnace.TheinfluencesofTiNcontentonmechanicalpropertiesandelectricalconductivityofTiN-Al2O3compositeswerestudied.TheresultsshowedthatthemechanicalpropertiesofthecompositeincreasedwithTiNcontentincreasing,whiletheresistivityofcompositesdecreased.Acompositewith40%TiNhad498MPabendingstrength,4.285MPa·m1/2fracturetoughness,1.34×10-3Ω·cmresistivity.TheSEManalysisshowedthatthefineTiNcrystalsdistributedamongthecrystalboundaryofAl2O3matrix.Theybondedtogetherforminganet-likestructurewhichplayedaroleofrestrainingAl2O3grainsfromgrowingup,tougheningandstrengthening,sothemechanicalpropertiesofTiN-Al2O3compositewereenhanced.