简介：Theeffectsofdilatationalphasetransformationonthetargetstrengthofceramicmateri-alsareinvestigatedbasedonTate’smodel.Theconstitutivebehaviorofmaterialsindifferentregions(elastic,cracked,plasticandphasetransformation)aretakenintoaccount.Itisfoundthat,withaproperchoiceofmaterialparameters,thedilatationalphasetransformationcanincreaseeffectivelythetargetstrengthR_t.Thiswouldbeofimportanceinpenetration-resistancedesign.

简介：Moleculardynamics(MD)simulationswereperformedtostretchtherectangulargraphenesheetsdopedwithsilicon,nitrogenorboronatoms.Young’smodulus,ultimatestress(strain)andenergyabsorptionweremeasuredforthegraphenesheetswiththedopingconcentration(DC)rangingfrom0to5%.Theemphasiswasplacedonthedistincteffectsofeachindividualdopantonthefundamentalmechanicalpropertiesofgraphene.TheresultsindicatedthatincorporatingthedopantsintographeneledtoanalmostlineardecreaseinYoung’smodulus.Monotonicreductionsinultimatestrength,ultimatestrainandenergyabsorptionwerealsoobserved.Suchdopingeffectswerefoundtobemostsignificantforsilicon,lesspronouncedforboron,andsmallornegligiblefornitrogen.Theoutputsprovideanimportantguidanceforthedevelopmentandoptimizationofnovelnanoscaledevices,andfacilitatethedevelopmentofgraphene-basedM/NEMS.

简介：Themechanicalperformanceofcarbonnanotube(CNT)reinforcedpolymercompositesisprimarilycontrolledbythedispersivecapacityandinterfacialshearstrengthofCNTsinpolymermatrices.CNTfunctionalizationswillimprovedispersionandstrengtheninterfacialbondingofCNTsinmatrices.TounderstandtheeffectsofdifferentfunctionalizationschemesontheinterfacialstrengthofCNT-polymercomposites,pulloutofthecovalent,noncovalent,andmixedfunctionalizedsingle-walledcarbonnanotube(SWCNT)frompolyethylene(PE)matrixwassimulatedbyusingmoleculardynamics,respectively.TheresultsshowthattheSWCNT-PEinterfacialshearstrengthissignificantlyimprovedbySWCNTfunctionalizations,particularlybymixedfunctionalization.

简介：Basedonthecommercialcomputationalsoftware,athree-dimensionalfiniteelementmodeltosimulatethethermo-mechanicalbehaviorsinanuclearfuelrodisestablished;Bytakingintoconsiderationirradiation-swellingofthepelletandtheirradiationdamageeffectsinthecladdingtogetherwiththecouplingeffectsbetweenthetemperaturefieldandthemechanicalfield,theusersubroutinestodefinethespecialmaterialperformanceandboundaryconditionshavebeendevelopedindependentlyandvalidated.Three-dimensionalnumericalsimulationofthethermo-mechanicalcouplingbehaviorsinanuclearfuelrodiscarriedout,andtheevolutionrulesoftheimportantthermalandmechanicalvariablesareobtainedandanalyzed.Theresearchresultsindicatethat:(1)thefuelpelletswillbeincontactwiththecladdingathighburnup,whichwillinduceastrongmechanicalinteractionbetweenthem;(2)theirradiationcreepeffectplaysanimportantroleinthemechanicalbehaviorevolutioninthenuclearfuelrod.

简介：thehydroxya-patite粒子的机械性质上的水吸着的损坏效果增强了Bis-GMA/TEGDMA共聚物(HA/Bis-GMA/TEGDMA)用3D被预言了有限房间模型。聚合物矩阵上的可塑剂效果被看作它的幼仔的模量的一个变化。三个不同房间模型被用来决定在debondingdamage上改变粒子内容，分裂期间力量和潮湿集中的影响。压力分发模式被检验了，压力转移模式澄清了。幼仔Bis-GMA/TEGDMA的模量和破裂力量合成也有或没有损坏的考虑用模型被预言。有thedebonding损坏的考虑的以前的结果在对存在文学的好同意是试验性的数据。我们的建议模型和一条其他的途径的防护效果被讨论。FCC房间模型也被扩大了预言批评负担为损坏并且undamaged合成题目到3点曲折测试。

简介：Amethodisdevelopedforcyclicelastoplasticanalysisacrossmicro/meso/macroscaleswhichiseffectiveforthequantitativetransitionofphysicalvariablesandforevaluatingthesizeeffectsofmicrostruc-tures.Byusingtheimprovedself-consistentsehemeproposedbyFanandcarryingoutadelicatemesoscop-icanalysisbasedonashear-lagmodel,thesizeeffectsincludingthethicknessofhardandsoftlayersrelativetotheinclusiondimensionareobtainedontheoverallelastoplasticresponsesofmaterialsupto50cycles.Thedominantcharacteristicsoftheanalysisrarethatthecharacteristicdimensionsofamicrostructuresuchasthethicknessofthelayersandtheinclusiondimensioncanbeexplicitlyincorporatedintotheformulation.Resultsofnumericalanalysisusingonly4plasticconstantsshowthatthethickerthelayerrelativetothein-clusionsize,thesofterthematerialinproducingmoreplasticstrainvaluesforagivenappliedstressampli-tude.Thisisinagreementwiththewell-knownexperimentalrulethattheyieldstrengthoflayeredstructuresisinverselyproportionultothesquarerootofthespacingbetweenlayers.Itisfoundthatratchetingdependsverymuchonthesizeofthelayered-structureandthatthethinnertherelativethicknessofthelayerthelesstheratchetiugdisplacement.Thisfindingmaybeusedtoexplainwhyphenomenologicalmodelsonratchetingarenotquitesuccessfulsofar,indicatingthesignificanceofaerossscaleanalysisinunderstandingissueswhichhaveexistedforalongtime.

简介：Westudyelectromechanicalfieldsintheanti-planedeformationofaninfinitemediumofpiezoelectricmaterialsof6mmsymmetrywithacircularcylindricalhole.Thetheoryofelectroelasticdielectricswithelectricfieldgradientintheconstitutiverelationsisused.Specialattentionispaidtothefieldsnearthesurfaceofthehole.

简介：生长一延长或过寺院生活椭圆形在纤维微虚空矩形的薄板使遭到了到单轴的延期的增强的各向异性的不可压缩的超在有限弹性的框架以内被学习。在虚空的生长上联合空形状和空尺寸的效果被付特殊注意到。有孤立的椭圆形的虚空的板的变丑功能被给参数，它被二表示解决微分方程。答案近似从最小的势能原则被获得。为有虚空的表面上的大量空方面比率和压力分布的虚空的变丑曲线被数字计算获得了。虚空的生长行为和虚空的表面上的压力分布的特征被捕获。在薄板中的虚空的生长上的空尺寸和空形状的联合效果被讨论。为有不同尺寸和不同空方面比率的虚空的最大的压力被比较。