Mackenzieetal.Thedeformation,recrystallisationandtextureofthreemagnesiumalloyextrusions
2EBSDimageshowingmicrostructureofAZ31following
extrusionat282uC:smallgrainscircledareassociated
withhighdensityof
LABs
TheEBSDorientationmicrographinFig.2showsthe
microstructureofAZ31followingextrusionat282uC.
Thelargegraininthecentreofthemicrographisnot
equiaxed;itstretchesfromthetoptothebottomofthe
image.Thesmallrecrystallisedgrainscircledinthe
centreofthemicrographareadjacenttoahighdensity
ofLABsintheunrecrystallisedregion.
ThemicrostructureofZC71followingextrusionat
270uCisshownintheEBSDorientationmicrograph
3EBSDimageshowingmicrostructureofZC71following
extrusionat270uC:smallrecrystallisedgrainsringed
intoprightofimageareassociatedwithHABs;sub-
grainswithinunrecrystallisedgrainareringedinbot-
tomleftof
image4EBSDimageshowingmicrostructureofWE43follow-ingextrusionat360uC:deformationheterogeneitiesareindicatedbyarrows;smallrecrystallisedgrainsringedareassociatedwith
heterogeneitiespresentedinFig.3.ThelargeunrecrystallisedgrainscontainLABsandsubgrains,whicharecircledinthebottomleftoftheimage.ExamplesofLABsthatdissecttheunrecrystallisedgrainsareindicatedbyarrows.Inthetoprightofthemicrographsmallrecrystallisedgrainsareringed;theseareassociatedanHAB.ThemicrostructureofWE43followingextrusionat360uCisshownintheEBSDorientationmicrographspresentedinFigs.4and5.InFig.4,HABsthatcrosstheunrecrystallisedregionareindicatedwitharrows;thesmallgrainsringedareassociatedwiththeHABs.InFig.5,smallgrainsareassociatedwiththesecondphaseparticlesinthecentreofthemicrograph.AnnealedmicrostructuresDuringannealingfor24hat435uCthemicrostructuresofAZ31andZC71fullyrecrystallised;theMLIgrainsizesintheannealedalloyswere25and55mmrespectively.Duringannealingfor24hat525uC
the5EBSDimageshowingmicrostructureofWE43follow-ingextrusionat360uC:mostofsmallrecrystallisedgrainsareassociatedwithsecondphaseparticles
MaterialsScienceandTechnology2007VOL23NO101175