Core-shell structures and precipitation kinetics of Al3(Sc,Zr) L12 intermetallic phase in Al-rich alloy.

V. RADMILOVIC; A. TOLLEY; Z. LEE; U. DAHMEN

Zlatibor

Conferencia; 4th Balcan Conference on Metallurgy, 2006.; 2006

While binary Al-Sc alloys form Al3Sc intermetallic precipitates, ternary Al-Sc-Zralloys develop precipitates that contain both Sc and Zr. Electron microscopycharacterization using Z-contrast imaging indicates rapid initial formation of Al3(Sc,Zr) precipitates with a Sc-rich core followed by the slower development of a Zr-rich Al3(Zr,Sc) shell. The shell acts as a diffusion barrier, slowing down the rate of precipitate coarsening.