The multiple twinning of Fe4Al13 as a heterogeneous phase in commercial AlZnMgCu alloys

Abstract

The heterogeneous phase in commercial AlZnMgCu alloys has been studied using transmission electron microscopy. It is found that Fe₄Al₁₃ is the main constituent phase, in which multiple twins are frequently observed. Twinning planes are (200) and $\text{(20}\text{1}\text{)}$. The orientation relationship of neighbouring twins can be equivalently considered to rotate 2π/10 about [010]. A selected area diffraction pattern with tenfold symmetry has been recorded and is discussed in relation to quasi-crystals.