Al-Zn(Cu)合金的相变和Al-Zn-Cu系相图

Al-Zn-Cusystemistheimportantbasisfor practicalAlalloysandZnalloys[1].Amiscibility gapofthefccphaseexistsabove277℃inthe Al Znsystem[2].Thealloywhosecompositionis atthetopofthemiscibilitygapiscalledsym metricalalloyAlZn.Thisalloyhasmanytypical properties.Theimportantoneisthatthespi nodaldecompositioneasilytakesplaceinit.In ordertoavoidthedecomposition,Cuhasbeen added,whichiseffective.Additionof2%Cu molefractioncoulddelaythespinodaldecompo sitionfortwogrades[3,4].AlZn 2Cuisanalloy which…

Phase transformation of Al-Zn (Cu) alloys and the phase diagram of Al-Zn-Cu system

The room temperature phase diagram of Al-Zn-Cu system is the important basis for judging the phase constituents of the materials at the usage condition. New results about the room temperature phase diagram of the low copper side in the Al-Zn-Cu systems have been shown in this study. Miscibility gap of fcc phase in the Al-Zn-Cu system has also been studied by experimental diffusion-couple method and thermodynamic calculation. Properties of this miscibility gap have been known. It is practically significant for the study on the aging behavior and for the control of the microstructure and properties of the Al alloys with Zn and Cu element.