资源描述：
《铝合金的熔炼与铸造（melting and casting of aluminum alloy）》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、铝合金的熔炼与铸造（Meltingandcastingofaluminumalloy）MeltingandcastingMeltingandpouringofaluminumalloyisthemainlinkincastingproduction.Strictcontrolofthewholeprocessofmeltingandcastingplaysanimportantroleinpreventingcastingdefectssuchaspinholes,inclusions,undercasting,cracks,
2、poresandshrinkageporosity.Duetothelargehydrogenabsorptiontendency,strongoxidationabilityandeasydissolutionofiron,aluminummeltmustadoptsimpleandcautiouspreventivemeasurestoobtainhighqualitycastingsduringmeltingandcastingprocess.1、aluminumalloyburdenpreparationandqual
3、itycontrolInordertosmelthighqualityaluminummelt,thequalifiedrawmaterialshouldbeselectedfirst.Tocarryoutscientificmanagementandproperprocessingofrawmaterials,otherwiseitwillseriouslyaffectthequalityofthealloy,theproductionpracticehasprovedthattherawmaterials(includin
4、gmetalmaterialsandauxiliarymaterials)laxcontrolwillmakebatchscrapcastings.(1)rawmaterialsmusthavequalifiedchemicalcompositionandorganization,andthespecificrequirementsareasfollows:Inadditiontotheanalysisofthemaincomponentsandimpuritiesinthealloyingots,thelowaccompan
5、ytissueandfracturearealsoexamined.Practicehasprovedthatitisdifficulttoobtaindensecastingsbyusingaluminumliquidwithseriousshrinkageholes,pinholesandbubbles,andevenscrapthewholefurnaceandthewholebatchofcastings.ItwasfoundinthestudyofAlSialloyingotsofAluminumAlloypinho
6、le,doesnotappearinthemoltenpuresandcastingpinholetestblock,whenthealuminumsiliconalloyingotwithlowandunqualifiedspecimens,pinholeserious,andthegrainsizelarge.Thereasonistheheredityofthematerial.TheheredityofAlSialloyandheredityincreasedwiththeincreaseofcontentandthe
7、amountofsiliconwas7%.Continuetoincreasesiliconcontenttoeutecticcomponent,geneticdecreaseslightly.Inordertosolvethecastingdefectscausedbytheheredityoftheburden,aluminumingots,masteralloysandothermaterialswithhighmetallurgicalqualitymustbeselected.Specificstandardsare
8、asfollows:(1)thereshouldbenopinholesandporesonthefracturesurfacePinholeshouldbewithinthreegrade,local(notmorethan25%oftheinspectedarea)sho
