X-ray powder diffraction study of few Al–4.5 at% Zn-x at% Mg alloys

Seven Al-4.5 at% Zn-x at% Mg alloys, with x ranging between 0 and 3.0, are studied by X-ray powder diffraction. The following measurements are performed: (i) the dependence of the lattice constant of the a-phase of the as-quenched and the slowly cooled alloys on x at RT, (ii) the thermal expansion of the equilibrium eta(MgZn2)-phase and its dissolution in the alpha-phase at elevated temperatures. It turns out that in particular the analysis of the lattice constant of the matrix, alpha, results in valuable information about the amount of solved atoms of the alloyed elements and the matrix stresses.