Al-6.3Zn-2.8Mg-1.8Cu铸造铝合金的组织和室温力学性能

48

2

Vol.48

No.2

20122

211—219ACTAMETALLURGICASINICAFeb.2012

pp.211–219

Al–6.3Zn–2.8Mg–1.8Cu

(

,

710072)

,

,Al–6.3Zn–(MgZn2)

Al–6.3Zn–2.8Mg–1.8Cu

.

2.8Mg–1.8Cu

,

α(Al)

α(Al)+η(MgZn2)

η

T

(Mg3ZnxCu3 xAl2)

Al7Cu2Fe.

,

η(MgZn2)

,

S

(Al2CuMg).

Al–6.3Zn–2.8Mg–1.8Cu

.

,

,

480MPa

490MPa,

0.2%

2.2%.

,

,

,

,

TG146.1

A

0412 1961(2012)02 0211 09

MICROSTRUCTURESANDROOMTEMPERATURE

MECHANICALPROPERTIESOFAl–6.3Zn–2.8Mg–1.8CuCASTINGALUMINUMALLOY

YANGGuangyu,MENGHongshuai,LIUShaojun,QIYuanhao,JIEWanqi

StateKeyLaboratoryofSolidi cationProcessing,NorthwesternPolytechnicalUniversity,Xi’an710072Correspondent:YANGGuangyu,professor,Tel:13679228998,E-mail:ygy@nwpu.edu.cn

SupportedbyNationalNaturalScienceFoundationofChina(No.51071129)andNationalBasicRe-searchProgramofChina(No.2011CB610400)

Manuscriptreceived2011–09–15,inrevisedform2011–12–21

ABSTRACTThemicrostructuresandroomtemperaturemechanicalpropertiesofmetal–mold–castingaluminumalloyAl–6.3Zn–2.8Mg–1.8Cuwerestudied.Itwasfoundthatthemicrostructureoftheas–castexperimentalalloyconsistsofnearequiaxedα(Al)matrix,α(Al)+η(MgZn2)eutecticandlittleAl7Cu2Feparticlephase.Thephaseconstitutionofthequenchedexperimentalalloywaschanged,theηphasewasdissolvedintoα(Al)matrixandtendedtodisappear,howeveranewphase,S(Al2CuMg),appeared,whichstillmainlydistributedalongtheα(Al)grainboundary.Theopti-mumsingle–agingprocessparametersweredeterminedbyinvestigatingagehardeningresponseoftheexperimentalalloy.Itwasfoundthatthedouble–agingprocesscouldmakethetensilestrengthoftheexperimentalalloyincreasefrom480MPato490MPa,andtheelongationfrom0.2%to2.2%,comparingwiththesingle–agingprocess.

KEYWORDSaluminumalloy,solutiontreatment,microstructure,agehardening,mechanical

propertyAl–Zn–Mg–Cu

*

,

,

,

,

[1 4]

.

51071129

2011CB610400

,

,

:2011–09–15,

:2011–12–21

,

,

+

:

,

,1967

,

,

[5,6]

.

DOI:10.3724/SP.J.1037.2011.00579Al–Zn–Mg–Cu

,

.