设计指南-模具设计(1)

Designguidecontentsupdaterelease05//1997aENDesignguideGEPlasticsrelease05//1997Contents1GeneralIntroduction1DesignDevelopment...............91.1Introduction..................................91.2Materialdesignfactors.......................91.3Developmentsteps...........................91.3.1End-userequirements......................91.3.2Preliminarydesign.........................101.3.3Materialselection.........................101.3.4Designmodification........................101.3.5CAD/CAE.................................101.3.5.1Flowanalysis............................101.3.5.2Stressanalysis...........................111.3.6Prototypingandtesting.....................111.3.7End-usetesting...........................112Designforstiffness................132.1Introduction..................................132.2Howtodeterminestiffness....................132.2.1Material.................................132.2.2Geometry&loading........................142.2.3Otherfactorsinfluencingstiffness............142.2.4Calculatingthestiffness....................152.2.5Modalanalysis............................152.2.6Safetyfactors.............................152.3Increasingpartstiffness......................152.3.1Ribs.....................................152.3.2V-grooves................................152.3.3Corrugation...............................162.4Optimizationofstiffness......................162.4.1Optimizationforpartweight.................162.4.1.1MaterialSelection........................162.4.1.2Geometricconsiderations..................162.4.2Optimizationforstiffnesstocostratio.........163Designforstrength................193.1Introduction..................................193.2MaterialStrength............................193.2.1Ultimatestrength..........................203.2.2Yieldstrength.............................20Designguide1Contents3.2.3Straintofailure...........................203.2.4Proportionallimit..........................203.2.5Materialtoughness........................203.2.6Othermeasures...........................203.3Effectsofvariousfactorsonstrenght...........203.3.1Otherfactors.............................203.4PartStrength.................................213.4.1Ultimatepartstrength......................213.4.2Partyieldstrength.........................223.4.3Parttoughness............................223.5Improvingpartstrength.......................223.5.1Materialchoice...........................223.5.2Geometryoptimization......................233.6Designconsiderations........................234Designforbehaviourovertime..254.1Introduction..................................254.2Statictimedependentphenomena..............254.2.1Creep...................................254.2.1.1Creeprecovery...........................264.2.1.2Creepfailuremodes.......................264.2.1.3Apparentmodulus........................264.2.2Stressrelaxation..........................274.2.3Designconsiderations......................284.3Dynamictimedependentphenomena...........284.3.1Fatigue..................................284.3.1.1Fatigueandendurancelimits................284.3.1.2Factorsaffectingfatigue...................294.3.2Wearresistance...........................294.3.2.1Typesofwear............................294.3.2.2Factorsaffectingwear.....................295Designforimpactperformance..315.1Introduction..................................315.2Commonimpacttestingmethods...............315.2.1Pendulummethods.........................325.2.2Fallingweightmethods.....................325.3Designconsiderations........................33Designguide1Contents6Designforappearance............356.1Introduction..................................356.1.1Generalremarks...........................356.2Surfacedefects..............................356.2.1Sinkmarks...............................356.2.2Weldlines...............................356.2.3Airtraps.................................356.2.4Voids....................................366.2.5Streaks..................................366.2.6Delamination.............................366.2.7Jetting..................................366.2.8Gatemarks...............................366.2.9Summary.................................377Designforprecision...............397.1Introduction..................................397.1.1Mouldshrinkage...........................397.1.2Secondaryeffects.........................397.2Shrinkagephenomena.........................397.2.1Cooling..................................397.2.2Packing..................................407.2.3Orientation...............................407.3Materialsandshrinkage.......................407.3.1Amourphousmaterials......................407.3.2Crystallinematerials.......................417.3.3Reinforcedmaterials.......................417.4Designrelatedfactors........................417.4.1Partwallthickness.........................417.4.2Ribs.....................................417.5Mouldrelatedfactors.........................417.5.1Gatelocation.....................