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WORKSHOPPRACTICESBASICSTEPS1.Designconcepts2.Selectionofmaterials3.ManufacturingDESIGNREQUIREMENTSObjectivestoachieveGeometry,SizeandfinishPrepareformanufacturingDrawing+Material•CommunicationofinformationShape,size,andfeatures•Universallanguageofengineering•GraphicalconstructionDRAWINGDrawing:InterpretationandcreationDimensioning:PropercommunicationTolerances:Manufacturer’slimitsDRAWINGSKILLSBASICINFORMATION•ProjectedViews:Showasmanyviewsshowingcompleteness.(Front,Side,Top,others.)•CrossSections:Aviewthatisgoodforshowinginteriorfeatures.•DIMENSIONS:MostimportantPROJECTIONS(Orthographicrepresentation)Front,Top,SideViews.Isometric.GRAPHICREPRESENTATIONTwo-dimensionalrepresentationofthree-dimensionalobjectsDIMENSIONSTobuildthestructureorfabricatepartsSimpleObject1SimpleObject2604030++++++++++ParallelDimensionsChainDimensionsSuperimposedDimensionsCombinedDimensionsCoordinateDimensionsDEFININGDIMENSIONSDIMENSIONINGFEATURESCirclesHolesRadiiTOLERENCESDimensionalTolerances+-GeometricTolerancesThemaximumpermissiblevariationfromthedimensionTYPESOFDRAWINGSLayout-PlacementsWorking-AssemblypartsSchematic/diagrammatic-UsingsymbolsPRODUCINGDRAWINGSManualorwithdrawinginstrumentsandOtheraidssuchastemplatesandappliqués,Freehandwithpencilonpaperorwithautomateddeviceslikecomputers.HandDrawingPencilsPens/InksChalkCrayonsDrawingPapersandSurfacesDrawingToolsandAccessoriesErasersDrawingToolsandAccessoriesCompassesCurvesDrawingBoardsLetteringStencilsandGuidesParallelRulesProtractors,Triangles,andCornerSquaresRulersandMeasurementToolsT-SquaresTemplatesMODERNAIDSComputerSoftwareComputerAidedDesign-CADSELECTIONOFMATERIALSClassificationofMaterialsBasedonthespecificapplicationStructuralmaterials(mechanicalparts)Functionalmaterials(electrical,optical,magnetic,...)REQUIREMENTSOFSTRUCTURALMATERIALSStiffnessResistancetoelasticdeformation(woodV/Splastic)StrengthResistancetoplasticdeformation(metalV/Saplastic)ToughnessResistancetofracture(plasticrulerV/Swoodormetal)ElectricalmaterialsConductors,insulators,dielectric…MagneticmaterialsRemanence,saturationmagnetization…OpticalmaterialsTransmission,reflection,refractionREQUIREMENTSOFFUNCTIONALMATERIALSCLASSIFICATIONOFENGINEERINGMATERIALSMetalsandAlloys:FerrousMetalsPossessgoodfunctionalandstructuralpropertiesExamplesLow,MediumandHighCarbonSteels(0.30to~2.0%)StainlessSteelcontainingatleast10.5%chromium.Non-FerrousMetalsPossessgoodfunctionalpropertiesExamplesAluminum/Aluminumalloys,Brass(copperandzinc,65%to35%)BronzeCeramicsandGlasses:WithstandHightemperature,usuallyverybrittleandpoorelectricalconductorsExamplesCrystalline(ceramics)-Alumina,Zirconia.Non-crystalline(glasses)-ENGINEERINGMATERIALSPolymers:Non-crystallineOrganicmaterialscontainingcarbon.Mostpolymersarepoorelectricalconductorsbutcorrosionresistant.ExamplesThermoplastic.Formedintodesiredshapesunderheatandpressure.(PVC),polycarbonate(PC),andpolystyrene(PS).polyethylene(PE),polypropylene(PP),polyesterThermosettingmaterials.FormedintodesiredshapesunderheatExamplesComposites:Highstiffness,HighstrengthandHightemperatureperformanceMaterialswheretwoormoreoftheabovematerialsarebroughttogetheronmacroscopiclevel.Usuallytheyconsistofamatrixandareinforcement.ExampleMetal-matrixcomposites(MMC)Polymer-matrixcomposites(PMC)Ceramic-...