機械設(shè)計外文翻譯

Aknowledge-basedsystemformaterialsselectioninmechanicalengineeringdesignS.M.SapuanAbstractThispaperstudiesvariousworkonthedevelopmentofcomputerizedmaterialselectionsystem.TheimportanceofKnowledge-basedsystem(KBS)inthecontextofconcurrentengineeringisexplained.ThestudyofKBSinmaterialselectioninanengineeringdesignprocessisdescribed.Thedevelopmentinmaterialsdatabases,whichsometimesserveasmaterialselectionpackages,isalsodiscussed.TheuseofKBSinmaterialselectionandtheapplicationinthedomainofpolymeric-basedcompositearechosenastypicalexamples.2001PublishedbyElsevierScienceLtd.1.IntroductionMaterialsselectionisatasknormallycarriedoutbydesignandmaterialsengineers.GutteridgeandWater-man[1]describedtheaimofmaterialsselectionastheidentificationofmaterials,whichafterappropriatemanufacturingoperations,willhavethedimensions,shapeandpropertiesnecessaryfortheproductorcomponenttodemonstrateitsrequiredfunctionatthelowestcost.Forthepurposeofmaterialselection,thousandsofdatawouldbeneededtocharacterizeallthegradesofmaterials.Manyselectionsystemsareavailabletohelpdesignengineerstochoosethemostsuitablematerials.Atthemostbasiclevel,designengineerscouldusetablesofmaterialpropertiesindatabooks.However,datasheetsareincompleteandoncepublished,theyaredifficulttoupdate.DoddandFairfull[2]describedhowinformationaboutengineeringmaterials,canbedividedintotwomaincategories,i.e.dataandknowledge.Dataisdefinedastheresultsofmeasurements,whereasknowledgerepresentstheconnectionsbetweenitemsofdata,thesourceofthisknowledge,whichcontributestoanunderstandingoftheresults.BoththecomputerizeddatabaseandtheKBSofmaterialselectionwillbedescribedinthefollowingsections.2.Thematerialdatabaseformaterialsselection2.1.SupportingdataandrigorouslogicforthehypothesisandobseruationInrecentyears,attentionisbeingmadetotheuseofcomputersystemstostoreandprocessdataregardingthepropertiesofmaterials.Itenablesthedesignerstoachievelargecapacityandrapidretrievalfromacomputerdatabasetoprovideeasyaccesstothematerialsdata.AccordingtoPrasad[3],materialsarethecommonelementsenumeratingpartsinaproductrealizationprocess.Nowadays,designengineersnormallyrelyonthematerialsthattheyarefamiliarwith.However,whendesignrequirementsexceedtheconstraintsofsuchmaterialsorexceedtheconstraintsonmaterialproperties,concurrentengineeringteamsmustconsideralternativematerials.Withdirectonlineaccesstoamaterialsdatabase,theconcurrentengineeringteamscouldselectmaterialsthatarelighter,strongerandlowerincost.Assumingthattheimpactofsuchsubstitutionscanbeanalyzedorsimulated,theteamscouldeasilymakeanoptimumselectionofmaterialsfortheavailableprocesses,conservematerialsforeachprocessandthus,reducematerialwaste.White[4]emphasizedtheimportanceofcomputeraidedmaterialsselectionasbookshaveseveraldrawbacksastheyareoftenoutdatedbeforereachingthebookshelves.Itisverydifficulttoindexthemtofindanswersortosortdatainthemannerofyourchoice.Acomputerizedsystem,whichprovidesaccesstomaterialsdata,isnotnecessarilyamaterialsselectionsystem,althoughaccesstodataisessentialtofacilitateselection.2.2.CriticalreviewThissectionreviewsthedevelopmentofcomputerizedmaterialsdatabasesthatenableddesignerstoselectthematerialsinmechanicalengineeringdesignapplication.ThedevelopmentofmaterialdatabaseshasbeenreportedbyHarmer[5],Breueretal[6-10],Baur[11-12],Michaeli[13],Ashby[14-15]andCebonandAshby[16-17].Harmer[5]reportedthatvariousdatabasesystemshavebeendevelopedforplastics,elastomersandrubberssuchastheCambridgeMaterialsSelector(CMS),CAMPUS,SelectorII,Plaspec,CenBASE/Materials,Mat.DB,PlasticsDesignLibrary.EngineeredMaterialsAbstracts,FUNDUS,ProspectorPlus,Polymat,SPAO,Pro-Concept,Explorer,Platt'Psolymerscan,StandardsInfodisk,PiraAbstracts,PackagingScienceandTechnologyAbstracts,Chem-IntellandWeldasearch.Computer-aidedmaterialpre-selectionbyuniformstandards(CAMPUS)isawidelyusedmaterialsdatabaseforplastics[6-10].AproductsimilartothatofCAMPUSisadatabaseconcernedwiththeselectionoflongfiberreinforcedplastics.ThissystemiscalledFUNDUSanditallowsthedistributionofmaterialinformationfromtheproducertothedesignerend-user[11-13].Assuch,itisofinteresttoallwhoworkwithsheetmoldingcompound(SMC),bulkmoldingcompound?.BMCorglass-matthermoplastic(GMT)materialsasreportedbyBaur[11-12]andMichaelietal.[13].CAMPUSandFUNDUShavefeatures,whichallowtheusertoviewallpropertiesforanylistedproduct,printthedataforanyproductsearchthedatabaseforproductssatisfyingspecificpropertyrequirements,selectandviewpropertiesforcomparison,andsortaccordingtospecificrequirementinascendingordescendingorder.Ashby[14,15]andCebonandAshby[16-17]developedacomputerizedmaterialsselectionsystemcalledCambridgeMaterialsSelector(CMS).Thesystemusesmaterialsselectioncharts,whichareawayofdisplayingmaterialpropertydatathroughtheuseofoptimizationprocedures.Theselectionprocessdependsonimplementingperformanceindices,acombinationofmaterialproperties,whichifmaximized,optimizesperformance.Thechartsaredevelopedtopresentthematerials,andtheperformanceindices,sothatthemostsuitableselectionofmaterialsandshapecanbecarriedout.機械工程設(shè)計選材基礎(chǔ)知識S.M.Sapuan摘要本文致力于研究對各種材料選擇的電腦化系統(tǒng)發(fā)展。并對以基礎(chǔ)知識的系統(tǒng)在并行工程環(huán)境（KBS）的重要性進行了解釋。KBS的研究在材料選擇方面由一個工程設(shè)計過程來描述。材料數(shù)據(jù)庫的發(fā)展，和選材服務(wù)，也被討論到了。在材料選擇KBS和使用中的聚合物基復合材料領(lǐng)域的應(yīng)用是選材典型的例子。2001年由Elsevier科學有限公司出版。1.簡介材料選擇通常是設(shè)計和材料工程師一項任務(wù)。加特里奇和水人[1]中是這樣描述選擇材料的:經(jīng)過適當?shù)闹圃鞓I(yè)務(wù)，將有尺寸，形狀和性能的產(chǎn)品或組件要以最低的成本展示其規(guī)定功能的材料選擇的目標。對于選材的目的，成千上萬的數(shù)據(jù)將需要所有的材料的特性。許多選擇系統(tǒng)可以幫助設(shè)計工程師選擇最合適的材料。在最基本的層面上，設(shè)計工程師可利用材料性能數(shù)據(jù)手冊表。但是，數(shù)據(jù)表是不完整的，一旦公布，他們是難以更新。多德和范福[2]描述了有關(guān)工程材料的資料，可分為兩大類，即數(shù)據(jù)和知識的分歧。數(shù)據(jù)被定義為測量的結(jié)果，而信息代表之間的數(shù)據(jù)，在這方面的知識，這有助于對結(jié)果的認識源項目的連接。無論是計算機化的數(shù)據(jù)庫和材料選擇的KBS將在以下各節(jié)描述。2.針對對材料選擇的材料數(shù)據(jù)庫2.1支持這一假設(shè)的數(shù)據(jù)和嚴密的邏輯近年來，關(guān)注正在面向計算機系統(tǒng)來存儲和處理數(shù)據(jù)的有關(guān)材料的性能。它使得設(shè)計者能夠在實現(xiàn)大容量和快速的從一個計算機數(shù)據(jù)庫里檢索到資料數(shù)據(jù)。據(jù)普拉薩德［3］，材料是在列舉部分產(chǎn)品實現(xiàn)過程的共同要素。如今，設(shè)計工程師通常依賴于材料，他們所熟悉的。然而，當超過設(shè)計要求這些材料的限制或超過材料特性的限制，并行工程團隊必須考慮替代材料。隨著直接在線訪問材料數(shù)據(jù)庫，并行工程團隊可以選擇的材料，重量更輕，更強，成本更低。假設(shè)，這種替代的影響可以分析或模擬，團隊可以輕而易舉地把一個可用進程的最佳選擇材料，節(jié)約每一個程序的材料，因此，減少材料浪費是必須的。白［4］強調(diào)了計算機選型輔助材料的重要性，圖書有幾個缺點，他們往往在到達的書架得時候已經(jīng)過時。這使得他們很難找到答案指標進行排序或在您選擇的方式的數(shù)據(jù)。電腦化系統(tǒng)，它提供了訪問數(shù)據(jù)的材料，并不一定是材料選擇系統(tǒng)，雖然對數(shù)據(jù)的訪問是必要的，以方便選擇。2.2嚴格審查本節(jié)回顧了計算機化的材料數(shù)據(jù)庫，使設(shè)計人員選擇了機械工程設(shè)計中的應(yīng)用材料的發(fā)展。材