外文翻译--机械工程设计选材基础知识.doc

英文原文AknowledgebasedsystemformaterialsselectioninmechanicalengineeringdesignAbstractThispaperstudiesvariousworkonthedevelopmentofcomputerizedmaterialselectionsystem.TheimportanceofKnowledgebasedsystemKBSinthecontextofconcurrentengineeringisexplained.ThestudyofKBSinmaterialselectioninanengineeringdesignprocessisdescribed.Thedevelopmentinmaterialsdatabases,whichsometimesserveasmaterialselectionpackages,isalsodiscussed.TheuseofKBSinmaterialselectionandtheapplicationinthedomainofpolymericbasedcompositearechosenastypicalexamples.2001PublishedbyElsevierScienceLtd.IntroductionMaterialsselectionisatasknormallycarriedoutbydesignandmaterialsengineers.GutteridgeandWaterman1describedtheaimofmaterialsselectionastheidentificationofmaterials,whichafterappropriatemanufacturingoperations,willhavethedimensions,shapeandpropertiesnecessaryfortheproductorcomponenttodemonstrateitsrequiredfunctionatthelowestcost.Forthepurposeofmaterialselection,thousandsofdatawouldbeneededtocharacterizeallthegradesofmaterials.Manyselectionsystemsareavailabletohelpdesignengineerstochoosethemostsuitablematerials.Atthemostbasiclevel,designengineerscouldusetablesofmaterialpropertiesindatabooks.However,datasheetsareincompleteandoncepublished,theyaredifficulttoupdate.DaddandFairfull2describedhowinformationaboutengineeringmaterials,canbedividedintotwomaincategories,i.e.dataandknowledge.Dataisdefinedastheresultsofmeasurements,whereasknowledgerepresentstheconnectionsbetweenitemsofdata,thesourceofthisknowledge,whichcontributestoanunderstandingoftheresults.BoththecomputerizeddatabaseandtheKBSofmaterialselectionwillbedescribedinthefollowingsections.Thematerialdatabaseformaterialsselection2.1.Supportingdataandrigorouslogicforthehypothesisandobservation.Inrecentyears,attentionisbeingmadetotheuseofcomputersystemstostoreandprocessdataregardingthepropertiesofmaterials.Itenablesthedesignerstoachievelargecapacityandrapidretrievalfromacomputerdatabasetoprovideeasyaccesstothematerialsdata.AccordingtoPrada3,materialsarethecommonelementsenumeratingpartsinaproductrealizationprocess.Nowadays,designengineersnormallyrelyonthematerialsthattheyarefamiliarwith.However,whendesignrequirementsexceedtheconstraintsofsuchmaterialsorexceedtheconstraintsonmaterialproperties,concurrentengineeringteamsmustconsideralternativematerials.Withdirectonlineaccesstoamaterialsdatabase,theconcurrentengineeringteamscouldselectmaterialsthatarelighter,strongerandlowerincost.Assumingthattheimpactofsuchsubstitutionscanbeanalyzedorsimulated,theteamscouldeasilymakeanoptimumselectionofmaterialsfortheavailableprocesses,conservematerialsforeachprocessandthus,reducematerialwaste.White4emphasizedtheimportanceofcomputeraidedmaterialsselectionasbookshaveseveraldrawbacksastheyareoftenoutdatedbeforereachingthebookshelves.Itisverydifficulttoindexthemtofindanswersortosortdatainthemannerofyourchoice.Acomputerizedsystem,whichprovidesaccesstomaterialsdata,isnotnecessarilyamaterialsselectionsystem,althoughaccesstodataisessentialtofacilitateselection.2.2.CriticalreviewThissectionreviewsthedevelopmentofcomputerizedmaterialsdatabasesthatenableddesignerstoselectthematerialsinmechanicalengineeringdesignapplication.ThedevelopmentofmaterialdatabaseshasbeenreportedbyHarmer5,Breueretal610,Baur1112,Michael13,Ashby1415andCebonandAshby1617.Harmer5reportedthatvariousdatabasesystemshavebeendevelopedforplastics,elastomersandrubberssuchastheCambridgeMaterialsSelectorCMS,CAMPUS,SelectorII,Specula,Cenbase/Materials,Mat.DB,PlasticsDesignLibrary.EngineeredMaterialsAbstracts,FUNDUS,ProspectorPlus,Polymat,SPAO,ProConcept,Explorer,Platapolymerically,StandardsInfodisk,PiuraAbstracts,PackagingScienceandTechnologyAbstracts,ChemIntellandWeldasearch.ComputeraidedmaterialpreselectionbyuniformstandardsCAMPUSisawidelyusedmaterialsdatabaseforplastics610.AproductsimilartothatofCAMPUSisadatabaseconcernedwiththeselectionoflongfiberreinforcedplastics.ThissystemiscalledFUNDUSanditallowsthedistributionofmaterialinformationfromtheproducertothedesignerenduser1113.Assuch,itisofinteresttoallwhoworkwithsheetmoldingcompoundSMC,bulkmoldingcompound.BMCorglassmatthermoplasticGMTmaterialsasreportedbyBaur1112andMichaelietal.13.CAMPUSandFUNDUShavefeatures,whichallowtheusertoviewallpropertiesforanylistedproduct,printthedataforanyproductsearchthedatabaseforproductssatisfyingspecificpropertyrequirements,selectandviewpropertiesforcomparison,andsortaccordingtospecificrequirementinascendingordescendingorder.Ashby14,15andCebonandAshby1617developedacomputerizedmaterialsselectionsystemcalledCambridgeMaterialsSelectorCMS.Thesystemusesmaterialsselectioncharts,whichareawayofdisplayingmaterialpropertydatathroughtheuseofoptimizationprocedures.TheselectionprocessdependsonimplementingperformanceIndices,acombinationofmaterialproperties,whichifmaximized,optimizesperformance.Thechartsaredevelopedtopresentthematerials,andtheperformanceIndices,sothatthemostsuitableselectionofmaterialsandshapecanbecarriedout.MachineDesignThecompletedesignofamachineisacomplexprocess.Themachinedesignisacreativework.Projectengineernotonlymusthavethecreativityinthework,butalsomustinaspectandsoonmechanicaldrawing,kinematics,engineeringmaterial,materialsmechanicsandmachinemanufacturetechnologyhasthedeepelementaryknowledge.Oneofthefirststepsinthedesignofanyproductistoselectthematerialfromwhicheachpartistobemade.Numerousmaterialsareavailabletotodaysdesigners.Thefunctionoftheproduct,itsappearance,thecostofthematerial,andthecostoffabricationareimportantinmakingaselection.Acarefulevaluationofthepropertiesofa.materialmustbemadepriortoanycalculations.Carefulcalculationsarenecessarytoensurethevalidityofadesign.Incaseofanypartfailures,itisdesirabletoknowwhatwasdoneinoriginallydesigningthedefectivecomponents.Thecheckingofcalculationsanddrawingdimensionsisofutmostimportance.Themisplacementofonedecimalpointcanruinanotherwiseacceptableproject.Allaspectsofdesignworkshouldbecheckedandrechecked.Thecomputerisatoolhelpfultomechanicaldesignerstolightentediouscalculations,andprovideextendedanalysisofavailabledata.Interactivesystems,basedoncomputercapabilities,havemadepossibletheconceptsofcomputeraideddesignCADandcomputeraidedmanufacturingCAM.Howdoesthepsychologistfrequentlydiscusscausesthemachinewhichthepeopleadaptsthemtooperate.Designspersonnelsbasicresponsibilityisdiligentlycausesthemachinetoadaptthepeople.Thiscertainlyisnotaneasywork,becausecertainlydoesnothavetoallpeopletosayinfactallisthemostsuperioroperatingareaandtheoperatingprocess.Anotherimportantquestion,projectengineermustbeabletocarryontheexchangeandtheconsultationwithotherconcernedpersonnel.Intheinitialstage,designsthepersonneltohavetocarryontheexchangeandtheconsultationonthepreliminarydesignwiththeadministrativepersonnel,andisapproved.Thisgenerallyisthroughtheoraldiscussion,theschematicdiagramandthewritingmaterialcarrieson.Iffrontsues,themachinedesigngoalistheproductioncanmeetthehumanneedtheproduct.Theinvention,thediscoveryandtechnicalknowledgeitselfcertainlynotnecessarilycanbringtheadvantagetothehumanity,onlyhaswhentheyareappliedcanproduceontheproductthebenefit.Thus,shouldrealizetocarriesonbeforethedesigninaspecificproduct,mustfirstdeterminewhetherthepeopledoneedthiskindofproductMustregardasthemachinedesignisthemachinedesignpersonnelcarriesonusingcreativeabilitytheproductdesign,thesystemanalysisandaformulationproductmanufacturetechnologygoodopportunity.Graspstheprojectelementaryknowledgetohavetomemorizesomedataandtheformulaismoreimportantthan.Themerelyservicedataandtheformulaisinsufficienttothecompletelydecisionwhichmakesinagooddesignneeds.Ontheotherhand,shouldbeearnestpreciselycarriesonalloperations.Forexample,evenifplaceswrongadecimalpointposition,alsocancausethecorrectdesigntoturnwrongly.Agooddesignpersonnelshoulddaretoproposethenewidea,moreoveriswillingtoundertakethecertainrisk,whenthenewmethodisnotsuitable,useoriginalmethod.Therefore,designsthepersonneltohavetohavetohavethepatience,becausespendsthetimeandtheendeavorcertainlycannotguaranteebringssuccessfully.Abrandnewdesign,therequestscreenabandonsobsoletelymany,knowsverywellthemethodforthepeople.Becausemanypersonofconservativeness,doesthiscertainlyisnotaneasymatter.Amechanicaldesignershouldunceasinglyexploretheimprovementexistingproductthemethod,shouldearnestlychooseoriginally,theprocessconfirmationprincipleofdesigninthisprocess,withhasnotunifieditaftertheconfirmationnewidea.中文译文机械工程设计选材基础知识摘要本文致力于研究对各种材料选择的电脑化系统发展。并对以基础知识的系统在并行工程环境（KBS）的重要性进行了解释。KBS的研究在材料选择方面由一个工程设计过程来描述。材料数据库的发展，和选材服务，也被讨论到了。在材料选择KBS和使用中的聚合物基复合材料领域的应用是选材典型的例子。2001年由Elsevier科学有限公司出版。1.简介材料选择通常是设计和材料工程师一项任务。加特里奇和水人1中是这样描述选择材料的经过适当的制造业务，将有尺寸，形状和性能的产品或组件要以最低的成本展示其规定功能的材料选择的目标。对于选材的目的，成千上万的数据将需要所有的材料的特性。许多选择系统可以帮助设计工程师选择最合适的材料。在最基本的层面上，设计工程师可利用材料性能数据手册表。但是，数据表是不完整的，一旦公布，他们是难以更新。多德和范福2描述了有关工程材料的资料，可分为两大类，即数据和知识的分歧。数据被定义为测量的结果，而信息代表之间的数据，在这方面的知识，这有助于对结果的认识源项目的连接。无论是计算机化的数据库和材料选择的KBS将在以下各节描述。2.针对对材料选择的材料数据库2.1支持这一假设的数据和严密的逻辑近年来，关注正在面向计算机系统来存储和处理数据的有关材料的性能。它使得设计者能够在实现大容量和快速的从一个计算机数据库里检索到资料数据。据普拉萨德3，材料是在列举部分产品实现过程的共同要素。如今，设计工程师通常依赖于材料，他们所熟悉的。然而，当超过设计要求这些材料的限制或超过材料特性的限制，并行工程团队必须考虑替代材料。随着直接在线访问材料数据库，并行工程团队可以选择的材料，重量更轻，更强，成本更低。假设，这种替代的影响可以分析或模拟，团队可以轻而易举地把一个可用进程的最佳选择材料，节约每一个程序的材料，因此，减少材料浪费是必须的。白4强调了计算机选型辅助材料的重要性，图书有几个缺点，他们往往在到达的书架得时候已经过时。这使得他们很难找到答案指标进行排序或在您选择的方式的数据。电脑化系统，它提供了访问数据的材料，并不一定是材料选择系统，虽然对数据的访问是必要的，以方便选择。