资源描述：
《热处理对A356 铝合金组织结构和力学性能的影响 毕业论文外文翻译》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、EffectofheattreatmentonmicrostructureandtensilepropertiesofA356alloysPENGJi-hua1,TANGXiao-long1,HEJian-ting1,XUDe-ying21.SchoolofMaterialsScienceandEngineering,SouthChinaUniversityofTechnology,Guangzhou510640,China;2.InstituteofNonferrousMetal,GuangzhouJinbangNonferrousCo.
2、Ltd.,Guangzhou510340,ChinaReceived17June2010;accepted15August2010AbstractTwoheattreatmentsofA356alloyswithcombinedadditionofrareearthandstrontiumwereconducted.T6treatmentisalongtimetreatment(solutionat535℃for4h+agingat150℃for15h).Theothertreatmentisashorttimetreatment(solu
3、tionat550℃for2h+agingat170℃for2h).TheeffectsofheattreatmentonmicrostructureandtensilepropertiesoftheAl-7%Si-0.3%Mgalloyswereinvestigatedbyopticalmicroscopy,scanningelectronicmicroscopyandtensiontest.Itisfoundthata2hsolutionat550℃issufficienttomakehomogenizationandsaturatio
4、nofmagnesiumandsiliconinα(Al)phase,spheroidofeutecticSiphase.Followedbysolution,a2hartificialagingat170℃isalmostenoughtoproducehardeningprecipitates.ThosesamplestreatedwithT6achievethemaximumtensilestrengthandfractureelongation.Withshorttimetreatment(ST),samplescanreach90%
5、ofthemaximumyieldstrength,95%ofthemaximumstrength,and80%ofthemaximumelongation.Keywords:Al-Sicastingalloys;heattreatment;tensileproperty;microstructuralevolution1IntroductionTheaging-hardenablecastaluminumalloys,suchasA356,arebeingincreasinglyusedintheautomotiveindustrydue
6、totheirrelativelyhighspecificstrengthandlowcost,providingaffordableimprovementsinfuelefficiency.EutecticstructureofA390canberefinedanditspropertiescanbeimprovedbyoptimizedheattreatment.T6heattreatmentisusuallyusedtoimprovefracturetoughnessandyieldstrength.Itisreportedthatt
7、hosefactorsinfluencingtheefficiencyofheattreatmentofAl-Sihypoeutecticalloysincludenotonlythetemperatureandholdingtime,butalsotheas-castmicrostructureandalloyingaddition.SomeT6treatmenttestmethodstandardsofA356alloysaremadeinChina,USA,andJapan,andtheyarewellaccepted.However
8、,theyneedmorethan4hforsolutionat540℃,andmorethan6hforagingat150℃,thuscausesubstantialener
