Investigation of phase equilibria in alloys of the Al–Zn–Mg–Cu–Zr–Sc system

Abstract

The phase equilibria in the multicomponent Al–Zn–Mg–Cu–Zr–Sc system have been studied in a composition range corresponding to compositions of commercial alloys. Differential thermal analysis, light microscopy, X-ray phase analysis and X-ray spectral analysis were used. The results of the investigation showed well-known intermetallic compounds in different combinations to be in equilibrium with the Al solid solution. The phases revealed were M and T in the Al–Zn–Mg–Cu system, W in the Al–Cu–Sc system and ZrAl3 and ScAl3. Isothermal and polythermal sections of the phase diagram have been constructed.