鎢合金桿彈侵徹復(fù)合靶板的實(shí)驗(yàn)和數(shù)值研究.pdf

1、中國(guó)科學(xué)技術(shù)大學(xué)博士學(xué)位論文鎢合金桿彈侵徹復(fù)合靶板的實(shí)驗(yàn)和數(shù)值研究姓名：許沭華申請(qǐng)學(xué)位級(jí)別：博士專業(yè)：工程力學(xué)指導(dǎo)教師：王肖鈞2000.6.1ABSTRACTInthethesis，themechanismofpenetrationoftungstenlong—rodisinvestigatedbyterminalballisticexperimentsThestaticanddynamicmechanicalbehaviorsofKe

2、vlarcompositelaminatesarestudiedbyMTSandSHPBAnewconstitutivemodelofKevlarcompositelaminatesexpressedasincrementalstress—strainrelationiSestablished，whichiseasyimplementedintothefiniteelementcomputationsThenumericalsimula

3、tionsoftungstenlong—rodspenetratingcompositeandsteeltargetarecarriedoutTheballisticexperimentsoftungstenlongrodspenetratingcompositelaminatesandsteeltargetareinvestigatedTheexperimentalresultsshowthatthepenetrationperfor

4、manceoftorquedlong—rodisstrongerthanthatofnontorquedrodThemetallographicinvestigationsofboththeresidualprojectilesandthefragmentspeeledoffrodsclearlyindicatethattheplasticdeformationoftorquedtungstengrainsisalmostalongth

5、eshearstressdirectionfortorquedrodsandSOthattheadiabaticshearingbandingformseasilyinthetorquedtungstenrodsduringpenetrationSothetorquedrodshavestrongerselfsharpeningeffectthanthenontorquedonesandthepenetrationperformance

6、oftorquedrodsisimprovedThedynamicmechanicalpropertiesofKevlarcompositelaminatesareinvestigatedTheexperimentalresultsshowthatthematerialhasdistiguishedratehardeninganddamagesofteningeffectsAnewconstitutivemodelthatincluds

7、rate—dependentinganddamagesofteningisproposedforKevlarcompositelaminatesThemechanicalpropertiesoftorquedmadnon—torquedtungstenalloyarealsoinvestigatedAconstitutivemodelthatdescribesratehardeningandstrainhardeningeffectsi

8、salsoestablishedforthesetungstenalloysThestress—straincurvesobtainedbythesemodelsagreewiththecorrespondingexperimentalcurveswellTheconstitutivemodelbasedonthemodificationofDmcker’SpostulateandtheoryofintemalvariablesiSdi

9、scussedThismodeliSabletocoverbothstableandunstablematerials，alsoisapplicabletobothelastic—plasticcouplinganduncouplingmaterialsSincetheloading／unloadingcriteriadescribedinloadingsurfaceandstrainincrements，itisveryconveni

10、enttoimplementthemodelintoanydynamiccomputationalprogramsFromthisconstitutivemodel，theconstitutiverelationofrate—dependenttransverselyisotropicmaterialsisestablishedThegoverningequationsofcontinuummechanicsandtheirfinite

11、elementdiscretizationmethodsinEulerianspacearedescribedTheformulationsoftriangularfiniteelementsinaxisymmetricC00rdinatesarediscussedandthenumericalflowchartisoutlinedBythetransverselyisotropicviscou—plasticconstitutiver