The deformation, recrystallisation and texture of three magn(4)

Mackenzieetal.Thedeformation,recrystallisationandtextureofthreemagnesiumalloyextrusions

6Inversepole guresforextrusionaxisdirectionshowingorientationsofunrecrystallisedandrecrystallisedregionsof

extrudedalloys:aAZ31unrecrystallised,bZC71unrecrystallised,cWE43unrecrystallised,dAZ31recrystallised,eZC71recrystallised,fWE43recrystallised

microstructureofWE43alsofullyrecrystallised.

TheMLIgrainsizeoftheannealedWE43was

y100mm,althoughsomegrainswere250to350mmindiameter.

Texture

OrientationdataofEBSDallowstheorientationsof

speci cregionsofthemicrostructuretobecharac-

terised.Theorientationsoftheunrecrystallisedand

recrystallisedregionsintheEBSDorientationmicro-

graphsofAZ31(inFig.2),ZC71(inFig.3)andWE43

(inFig.5)arerepresentedbytheinversepole gures

showninFig.6.Alloftheunrecrystallisedregions¯0.orientation:thebasal(Fig.6a–c)possessan,101¯0.directionsarealignedalongtheplanesand,101

extrusionaxis.IntherecrystallisedgrainsofAZ31¯0.texture(Fig.6d)andZC71(Fig.6e)astrong,101¯http://www.77cn.com.cnponentisaccompaniedbyaweaker,2

component.InWE43(Fig.6f)therecrystallisedgrains

haveaspreadoforientations,althoughthereisa

tendencyforthebasalplanestoorientateaty45utothe

extrusionaxis.

ThebulktexturesofAZ31,ZC71andWE43intheas

extrudedandannealedstatesaregivenbytheinverse

pole guresshowninFig.7.InAZ31andZC71thebasalplanesareorientatedparalleltotheextrusionaxis.¯http://www.77cn.com.cnponentisIntheextrudedconditionthe,101¯http://www.77cn.com.cnponent(Fig.7aaccompaniedbyaweaker,2andb);followingannealingfor24hat435uCthe¯http://www.77cn.com.cnponentisdominant(Fig.7dande).,2IntheasextrudedWE43therearetwotexturecomponents:oneisorientatedwiththebasalplanesandv1010-wdirectionparalleltotheextrusionaxis,theotherisorientatedwithbasalplanesaty45utotheextrusionaxis(Fig.7c).Afterannealingfor24hat525uCallbasalplanesareorientatedaty45utotheextrusionaxis(Fig.7f).MechanicaltestingThetensile/compressiveratios(asde nedbythe0?2%proofstresses)ofasextrudedandannealedAZ31,WE43andZC71aregiveninTable2.TheAZ31andZC71exhibitsomemechanicalasymmetryintheasextrudedstate;theasymmetryincreasedfollowingannealing.Microstructuralinvestigationofannealedspecimensrevealedextensivetwinningfollowingcompression,butnottensile,testing.TheWE43exhibitedverylittlemechanicalasymmetryineithertheasextrudedorannealedcondition.InWE43verylittletwinningwasobservedfollowingcompressiveortensile

testing.1176MaterialsScienceandTechnology2007VOL23NO10