简介：这篇论文认为在magneroelectroelastic联合由包括和矩阵组成的合成材料的多地是magnetoelectroelastic材料。机械，电并且在椭圆的柱体包括附近的磁场被复杂潜力提出。在包括内，种类，电并且磁场被发现一致并且与椭圆的形状变化。当包括被归结为一个裂缝时，，接口，种类，电场力量和磁场力量等于相应的遥远的，它能被用作边界条件。特殊情况软、透不过的包括，线包括和一个裂缝问题例如僵硬、可渗透的包括，详细被讨论。

简介：Themainobjectiveofthispaperistostudythesingularnatureofthecrack-tipstressandelectricdisplacementfieldinafunctionallygradientpiezoelectricmediumhavingmaterialcoefficientswithadiscontinuousderivative.Theproblemisconsideredforthesimplestpossibleloadingandgeometry,namely,theanti-planeshearstressandelectricdisplacementin-planeoftwobondedhalfspacesinwhichthecrackisparalleltotheinterface.Itisshownthatthesquare-rootsingularityofthecrack-tipstressfieldandelectricdisplacementfieldisunaffectedbythediscontinuityinthederivativeofthematerialcoefficients.Theprob-lemissolvedforthecaseofafinitecrackandextensiveresultsaregivenforthestressintensityfactors,elec-tricdisplacementintensityfactors,andtheenergyreleaserate.

简介：Thegrowthandcoalescenceoftwomicroholesincopperfoilwerestudiedexperimentallybyinsitutensiletestsundera,scanningelectronicmicroscope.Twomicroholesof15-35μmindi-ameterwerearrangedindifferentdistancesandorientations.Itwasfoundthatthemechanismsofmicroholeevolutionwererepresentedbyslippingbandcreation,andthencrackinitiationandpropagationalongtheslippingbands,inligament.Theprocessofmicroholegrowthandcoalescencewasinfluencedbytheinter-centerdistanceandorientationofmicroholes.Thecriticalsurfaceofmicroholesatcoales-cenceisabout2—2.5timesthatoftheinitialone.Thevariationofboththeintercenterdistanceandorientationdependsontheinitialangle.

简介：Theproblemofananti-planeGriffithcrackmovingalongtheinterfaceofdissimilarpiezoelectricmaterialsissolvedbyusingtheintegraltransformtechnique.Itisshownfromtheresultthattheintensityfactorsofanti-planestressandelectricdisplacementaroundthecracktiparedepen-dentonthespeedoftheGriffithcrackaswellasthematerialcoefficients.Whenthetwopiezoelectricmaterialsareidentical,thepresentresultwillbereducedtotheresultfortheproblemofananti-planemovingGriffithcrackinhomogeneouspiezoelectricmaterials.

简介：TheSelf-SimilarCrackExpansion(SSCE)methodisproposedtoevaluatestressintensi-tyfactorsatcracktips,wherebystressintensityfactorsofacrackcanbedeterminedbythecrackopeningdisplacementoverthecrack,notjustbythelocaldisplacementaroundthecracktip.Thecrackexpansionrateisestimatedbytakingadvantageofthecrackself-similarity.Therefore,theaccuracyofthecalculationisimproved.Thesingularintegralsoncracktipelementsarealsoanalyzedandarepre-ciselyevaluatedintermsofaspecialintegralanalysis.Combinationofthesetwotechniquesgreatlyin-creasestheaccuracyinestimatingthestressdistributionaroundthecracktip.Avarietyoftwo-dimen-sionalcracks,suchassubsurfacecracks,edgecracks,andtheirinteractionsarecalculatedintermsoftheself-similarexpansionrate.Solutionsaresatisfiedwitherrorslessthan0.5%ascomparedwiththeanalyticalsolutions.Basedonthecalculationsofthecrackinteractions,atheoryforcrackinteractionsisproposedsuchthatforagroupofalignedcracksthesummationofthesquareofSIFsattherighttipsofcracksisalwaysequaltothatatthelefttipsofcracks.ThistheorywasprovedbythemehtodofSelf-SimilarCrackExpansioninthispaper.

简介：基于Zak的压力功能，有V槽口的双性人材料的压力奇特的eigen方程被获得。为双性人材料的垂直界面的V槽口的压力紧张因素的一个新定义被提出。效果砍模量和泊松是矩阵材料的比率，特征值上的属于的材料被分析。为双性人材料的垂直V槽口的精明的KI的概括表情借助于压力推测被获得。槽口深度，槽口角度和泊松的效果是V槽口的尖端附近的单个压力地上的材料的比率与数字模拟系统地被分析。作为一个例子，有在单轴的一致紧张下面的两倍边槽口的一个有限盘子被介绍的方法和对压力奇特的槽口角度和泊松的比率的影响在槽口的尖端附近计算被获得。

简介：Formulationintermsofhypersingularintegralequationsfortheinteractionbetweenstraightandcurvedcracksinplaneelasticityisobtainedusingthecomplexvariablefunctionsmethod.Thecurvedlengthcoordinatemethodandasuitablenumericalschemeareusedtosolvesuchintegralsnumericallyfortheunknownfunction,whicharelaterusedtofindthestressintensityfactor,SIF.

简介：Thedynamicstressintensityfactorhistoryforahalfplanecrackinanotherwiseunboundedelasticbody,withthecrackfacessubjectedtoatractiondistributionconsistingoftwopairsofcombinedmodepointloadsthatmoveinadirectionperpendiculartothecrackedgeisconsidered.Theanalyticexpressionforthecombinedmodestressintensityfactorsasafunctionoftimeforanypointalongthecrackedgeisobtained.ThemethodofsolutionisbasedontheapplicationofintegraltransformtogetherwiththeWiener-HopftechniqueandtheCagniard-deHoopmethod.Somefeaturesofthesolutionarediscussedandgraphicalresultsforvariouspointloadspeedsarepresented.

简介：Twostochasticmodelsoffatiguecrackgrowthunderconstantamplitudecyclicloadingareproposedandstudiedbyusingthestochasticaveragingmethodandtotalprobabilitytheoremtoac-countforhighfrequencycomponentandlowfrequencycomponent,respectively,oftheirregularna-tureoffatiguecrackgrowthobservedinVirkler’sexperiment.Particularattentionispaidtothepredic-tionperformanceofthemodelsunderachangeintheinitialcracklength.Itisshownthatthemodelsproposedinthepresentpaperyieldsbetteragreementwithexperimentaldatathanothermodelsavail-ableinliterature.

简介：ThispaperpresentsanattemptattheapplicationofcatastrophetheorytothestabilityanalysisofJ-controlledcrackgrowthinthree-pointbendingspecimens.ByintroducingthesolutionsofJ-integralinthecompletelyyieldingstatefortheidealplasticmaterial,thecriticalconditionoflosingstabilityforthecrackpropagationinthespecimenisobtained,basedonthecuspcatastrophetheory.Theprocessofthecrackgrowthfromgeometricalsenseisdescribed.

简介：Thispaperpresentsanextensionofadisplacementdiscontinuitymethodwithcracktipelements(aboundaryelementmethod)proposedbytheauthorforfatiguecrackgrowthanalysisinplaneelasticmediaundermixed-modeconditions.Theboundaryelementmethodconsistsofthenon-singulardisplacementdiscontinuityelementspresentedbyCrouchandStarfieldandthecrack-tipdisplacementdiscontinuityelementsduetotheauthor.Intheboundaryelementimplementationtheleftorrightcrack-tipelementisplacedlocallyatthecorrespondingleftorrightcracktipontopofthenon-singulardisplacementdiscontinuityelementsthatcovertheentirecracksurfaceandtheotherboundaries.Crackgrowthissimulatedwithanincrementalcrackextensionanalysisbasedonthemaximumcircumferentialstresscriterion.Inthenumericalsimulation,foreachincrementofcrackextension,remeshingofexistingboundariesisnotrequiredbecauseofanintrinsicfeatureofthenumericalapproach.Crackgrowthismodeledbyaddingnewboundaryelementsontheincrementalcrackextensiontothepreviouscrackboundaries.Atthesametime,theelementcharacteristicsofsomerelatedelementsareadjustedaccordingtothemannerinwhichtheboundaryelementmethodisimplemented.Asanexample,thefatiguegrowthprocessofcracksemanatingfromacircularholeinaplaneelasticplateissimulatedusingthenumericalsimulationapproach.

简介：Fatiguecrackingtestsofasolderjointwerecarriedoutusingin-situscanningelectronmicroscopy(SEM)technologyundertensileandbendingcyclicloadings.Themethodforpredictingthefatiguelifeisprovidedbasedonthefatiguecrackgrowthrateofthesolderjoint.Theresultsshowthattheeffectoftheloadingtypeonthefatiguecrackgrowthbehaviorofasolderjointcannotbeignored.Inaddition,thefiniteelementanalysisresultshelpquantitativelyestimatetheresponserelationshipbetweensolderjointstructures.Thefatiguecrackinitiationlifeofasolderjointisingoodagreementwiththefatiguelife(N50%)ofatotallyelectronicboardwith36solderjoints.

简介：Basedonapproximatetheoreticalanalysesonatypiealsphericalcellcontainingasphericalmicrovoid,theinfluencesofmatrixmaterials’microscopicscaleonthemacroscopicconstitutivepotentialthe-oryofporousmaterialandmicrovoidgrowthhavebeeninvestigatedindetail.Byassumingthattheplasticde-formationbehaviorofmatrixmaterialsfollowsthestraingradient(SG)plastictheoryinvolvingthestretchandrotationgradients,theratio(λ=l/a)ofthematrixmaterials’intrinsiccharacteristicLengthltothemicro-voidradiusaisintrodncedintotheplasticconstitutivepotentialandthevoidgrrothlaw.Thepresentresultsindicatethat,whentheradiusaofmicrovoidsiscomparablewiththeintrinsiccharacteristiclengthlofthematrixmaterials,theinfluenceofmicroscopicsizeeffectonneithertheconstitutivepotentialnorthemicro-voidevolutionpredictedcanheignored.Andwhenthevoidradiusaismuchlagerthantheintrinsiccharac-teristiclengthlofthematrixmaterials,thepresentmodelcanretrogressautomaticallytotheimprovedGur-sonmodelthattakesintoaccountthestrainhardeningeffectofmatrixmaterials.

简介：这份报纸探索生长在生物软材料的导致的词法不稳定性。鉴于生活纸巾的生长不仅改变它的几何学而且罐头改变它的机械性质，我们建议在材料的机械性质上合并生长的效果的一个精制容量的生长模型。在这个容量的生长模型和常规热压力模型之间的类比为小、有限的变丑问题被探讨，它基于建议模型为有限元素分析带大容易。导致的生长的例子出现起皱在软composites的行为，包括核心壳软柱体和三分层的软纸巾，被探索。结果和讨论在理解在软生物纸巾的形态发生和生长之间的关联预见模型的可能的应用(例如皮肤和肿瘤)，以及在评估，变丑和软人工的材料的表面不稳定性行为由swelling/shrinkage导致了。

简介：Anasymptoticanalysisismadeonproblemswithasteady-statecrackgrowthcoupledwithacreeplawmodelundertensileloads.Asymptoticequationsofcracktipfieldsincreepmaterialsarederivedandsolvednumericallyundersmallscaleconditions.Stressandstrainfunctionsareadoptedunderapolarcoordinatesystem.Thegoverningequationsofasymptoticfieldsareobtainedbyinsertingthestressfieldandstrainfieldintothemateriallaw.Thecrackgrowthrateratherthanfracturecriterionplaysanimportantroleinthecracktipfieldsofmaterialswithcreepbehavior.

简介：Inthispaper,thescatteringofharmonicantiplaneshearwavesbytwofinitecracksisstudiedusingthenon-localtheory.TheFouriertransformisappliedandamixedboundaryvalueprob-lemisformulated.Thenasetoftripleintegralequationsissolvedusinganewmethod,namelySchmidt’smethod,ThismethodismoreexactandmorereasonablethanEringen’sforsolvingthiskindofproblem.Theresultofthestressnearthecracktipwasobtained.Contrarytotheclassicalelas-ticitysolution,itisfoundthatnostresssingularityispresentatthecracktip,whichcanexplaintheproblemofmacroscopicandmicroscopicmechanics.

简介：Inthispaper,thebehavioroftwocollinearcracksinmagneto-electro-elasticcompositematerialunderanti-planeshearstressloadingisstudiedbytheSchmidtmethodforpermeableelectricboundaryconditions.ByusingtheFouriertransform,theproblemcanbesolvedwithasetoftripleintegralequationsinwhichtheunknownvariableisthejumpofdisplacementsacrossthecracksurfaces.Insolvingthetripleintegralequations,theunknownvariableisexpandedinaseriesofJacobipolynomials.Numericalsolutionsareobtained.Itisshownthatthestressfieldisindependentoftheelectricfieldandthemagneticflux.

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。