资源描述:
《模具设计与制造专业英语 教学课件 黄义俊_ 电子教案统一模板(模具)Unit1.ppt》由会员上传分享,免费在线阅读,更多相关内容在应用文档-天天文库。
1、Unit1TheDieandMoldMaterialsandHeatTreatmentLesson1DieandMoldSteels1.1Lesson2ThePurposeofHeatTreatment1.2ReadingMaterials1CarbonSteelsandAlloySteels1.3ReadingMaterials2TypesofHeatTreatment1.41.1Lesson1DieandMoldSteelsThespecificmaterialselectedforaparticulardieormoldisnormallydeterminedbyth
2、emechanicalpropertiesnecessaryfortheproperoperationofthediesandmolds.Thesematerialsshouldbeselectedonlyafteracarefulstudyandevaluationofthefunctionsandrequirementsoftheproposedtool.Inmostapplications,morethanonetypeofmaterialwillbesatisfactory,andafinalchoicewillnormallybegovernedbytherequi
3、rementsfromcustomersfordiesandmolds,suchasperformanceandeconomicconsiderationsfordiesandmolds.Theprincipalmaterialsusedfordiesandmoldscanbedividedintotwomajorcategories:coldworktool(die)steelandhotworktool(mold)steel.Forexample,carbidesteel,alloytoolsteel,carbontoolsteel,high-speedsteel,hig
4、halloysteel,highcarbonsteel,lowcarbonsteel,shockresistancetoolsteelandsoon.Toproperlyselectadieormoldmaterial,thereareseveralphysicalandmechanicalpropertiesyoushouldunderstandtodeterminehowthematerialsyouselectwillaffectthefunctionandperformanceofthedieormold.[1]Physicalandmechanicalpropert
5、iesarethosecharacteristicsofamaterialwhichcontrolhowthematerialwillreactundercertainconditions.Physicalpropertiesarethosepropertieswhicharenaturalinthematerialandcannotbepermanentlyalteredwithoutchangingthematerialitself.Thesepropertiesinclude:weight,thermalandelectricalconductivity,rateoft
6、hermalexpansion,andmeltingpoint.Mechanicalpropertiesofamaterialarethosepropertieswhichcanbepermanentlyalteredbythermalormechanicaltreatment.Thesepropertiesinclude: strength,hardness,wearresistance,toughness,brittleness,plasticity,ductility,machinability,malleability,andmodulusofelasticity.F
7、romausestandpoint,dieandmoldsteelsareutilizedinworkingandshapingbasicmaterialssuchasmetalsandplasticsintodesiredforms.Fromausefulnessstandpoint,diesteelsareoftheperformancewhicharecapableofbeinghardenedandtemperedandwearresistance,highhardness,sufficient