简介:Themicrostructuresaftercastingandextruding,themechanicalpropertiesandelectricalconductivityafterRRAtreatmentofconventionalDCcastingandlowfrequencyelectromagneticcasting(LFEC)7075aluminumalloywereinvestigated.TheresultsshowedthatfinergrainswhichdistributedmorehomogeneouslywasobtainedinLFECingotscomparedwiththoseconventionalDCingots.TheextrudedbarsofLFECalloykeptitsfinegrainfeaturesoforiginalas-caststructure.IntheRRAtreatment,withtheextensionofsecondagingtime,thetensilestrengthandhardnessofalloydecreased,buttheelectricalconductivityincreased.Meanwhile,asthesecondagingtemperatureraised,thephasechangerateinprecipitationalsoincreased.Underthesameconditions,extrudedbarsofLFECalloyhadbetterperformancethanthatofconventionalDCcastalloy.TheoptimumRRAheattreatmentprocesswas120℃/24h+180℃/30min+120℃/24h.TheLFECextrudedbarsacquiredtensilestrength676.64MPa,hardness198.18,andelectricalconductivity35.7%IACSrespectively,whichwerehigherthanthatintheT6temper,indicatingthatanotableRRAresponsetakesplaceinLFECextrudedbars,whosesecond-stepretrogressiontimewas30min,anditwassuitableformassproduction.
简介:Fe61Co10Zr5W4B20体积有2公里的一条直径的金属性的玻璃(BMG)被使用铜模子吸扔准备。X光检查衍射(XRD),微分扫描热量测定(DSC),微坚硬并且压缩测试被采用调查结构,热稳定性,特别热处理在上的效果微坚硬并且这BMG的压缩力量。大约1207Hv和压缩微坚硬的BMG展览折断大约1707.6MPa的力量。在在结晶化温度的发作下面被退火以后,微坚硬几乎保持不变。但是在在结晶化温度的山峰上面被退火以后,微坚硬第一增加然后与退火的延伸逐渐地衰退时间。然而,为时间的一样的时期退火了,有退火的上升的微坚硬的愿望增加温度,当压缩破裂力量将显然减少时。
简介:Inducedembryonicstemresourcesfortheobservationofthecell(ES)cellsareexpectedtobepromisingcellbehaviorsindevelopmentalbiologyaswellastheimplantationincelltreatmentsinhumandiseases.ArecombinantE-cadherinsubstratumwasdevelopedasacellrecognizablesubstratumtomaintaintheEScells'self-renewalandpluripotencyatsinglecelllevel.Furthermore,thegenerationofvariouscelllineagesindifferentgermlayers,includinghepaticorneuralcells,wasachievedonthechimericproteinlayerpreciselyandeffectively.Theinductionandisolationofspecificcellpopulationwascarriedoutwiththeenhancingeffectofotherartificialextracellularmatrices(ECMs)inenzyme-freeprocess.ThemurineEScell-derivedcellsshowedhighlymorphologicalsimilaritiesandfunctionalexpressionstomaturedhepatocytesorneuralprogenitorcells.
简介:Aporosity-freeandcontamination-freesurfacelayerwithgrainsizesrangingfromnanometertomicrometerinFesampleswasobtainedbysurfacemechanicalattritiontreatment(SMAT)technique.MechanicalandwearpropertiesofthesurfacelayerintheSMATedandannealedFesamplesweremeasuredbymeansofnanoindentationandnanoscratchtests,respectively.ExperimentalresultsshowedthatthehardnessofthesurfacelayerintheSMATedFesampleincreasedevidentlyduetothegrainrefinement.TheelasticnoduliofthesurfacelayersintheSMATedandannealedFesampleswereunchanged,independentofgrainsizeinthepresentgrainsizeregime.ComparedwiththeoriginalFesample,thewearresistanceenhancedandthecoefficientoffrictiondecreasedinthesurfacelayeroftheSMATedFesample.
简介:TheAlNp/2024compositewithahighvolumefraction(50%)wasfabricatedbysqueezecasting.Itsmechanicalpropertieswereinvestigatedbytensiletestsatambienttemperatureandthemicrostructurewasobservedbyatransmissionelectronmicroscope(TEM).ItwasindicatedthataftersixthermalcoolingcyclestreatmenttheAIN/2024Alcompositeexhibitedhigherelasticlimit(σ0.01),tensilestrength(UTS)andelasticmodulus(E).TEMobservationshowedthattherewashigherdislocationdensitybothinthematrixandtheparticle.δ′phaseisthemainlyprecipitate.
简介:ConstantloadtestsinNS4solutionpurgedwithN2-5%CO2gasmixturewereconductedonAmericanPetroleumInstitute(API)X80pipelinesteelappliedinthe2ndWest-EastGasPipelineprojectwithandwithoutpreload.TheresultsshowthatcrackscouldinitiateandpropagateinX80pipelinesteelinnear-neutralpHenvironmentunderaconstantloadcondition.Thelifeofcrackinitiationandpropagationincreasedwithdecreasingappliedstress.Preloaddidnotchangeitscorrosionbehaviorobviously.However,preloadreducedthetimeforcrackinitiation.
简介:有激光的2205双不锈钢的焊接关节的电气化学的腐蚀行为连续的热处理被调查。第二等的奥氏体形成在热处理和在焊接材料上有最重要的效果的连续的热处理的结果期间是合金的热力学的平衡违犯的结果。铬和铝以及铁酸盐和奥氏体的体积部分的划分行为在单个阶段的作文上有显著影响。激光trated焊接的机械检查证明张力的力量和收益力量与增加第二等的奥氏体的数量增加。这被显示出对待激光的焊接是的6kW的最终的张力的强度更高大约20MPa能比没有热处理焊接和韧性进一步没有损害强度,改善了。结果显示因为不同柱子热处理力量,焊接改变腐蚀行为,宽广活跃山峰是没识别哪个被归因于溶解第二等在铁酸盐阶段奥氏体。贱金属和6kW焊接的pitting抵抗等价物(PRE)价值比另外的焊接的高,这被显示;贱金属是33.7,6kW焊接33.3,没有处理32.4,4kW焊接32.8,8kW焊接32.5。处理主要是的在再热以后的腐蚀抵抗改进的程度从以铁酸盐为主要成的区域由氮的移动引起了,它作为第二等的奥氏体生长的后果发生了。
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简介:Nanocrystallinesurfacelayersandgradientnanostructurein5182aluminumalloyhavebeenproducedthroughsurfacemechanicalattritiontreatment(SMAT).Theresultsindicatethatthegradientnanostructurecannotonlyimprovethemechanicalpropertiesof5182Alalloy,butalsohasacertaineffectonthePortevin-LeChatelier(PLC)effect.Theyieldandultimatetensilestrengthof5182AlalloywithSMATaresignificantlyimprovedcombiningwiththedecreaseoffractureelongationcomparedwiththeas-receivedone.ThePLCeffectof5182AlalloycouldbeeffectivelypostponedbytheformationofgradientnanostructureafterSMAT,ItleadstotheincreaseofcriticalstrainofthePLCeffect,moreconcentrateddistributionofserratedstrain,andincreaseofaveragestressamplitudeinspecialstrainrange.TheinfluenceofgrainsizeandgradientnanostructureonthePLCeffectof5182Alalloywasalsodiscussedindetail,Grainrefinementcouldsharplyincreasethedensityofdislocationsandhinderthemovementofdislocations,whichresultsinthedecreaseofmovingspeedofdislocationsandthemoreconcentrateddistributionofsoluteatoms.Thesoluteatomswouldaggregatetoformnanoprecipitatesandfurtherimpedemovementofdislocation.ThestrongerinteractionbetweenthedislocationsandthenanoprecipitatesisthemainmechanismofpostponedPLCeffect.
简介:Overcasting是过去常生产铝(固体)的一种新有点不一样的加入技术结合的/magnesium(液体)在这研究的二金属的材料。为Al/Mg(A390/AM60)二金属的样品,接口微观结构是研究点,它直接影响机械性质。因此,发现一个方法改进接口微观结构具有重要重要性。这研究在二金属的样品的A390/AM60接口微观结构上在液体Mg合金和热处理在钙(Ca)的效果上集中了增加。严峻的结果证明与在AM60的Ca增加,由于二个可能的原因,接口微观结构和A390/AM60二金属的样品的shear力量能被改进。热处理能进一步由溶解-Mg17Al12进-Mg并且破坏Mg2Si层结构。