Fundamental understanding of Na-induced high temperature embrittlement in Al–Mg alloys

摘要: Sodium is an undesirable impurity in aluminium–magnesium alloys. In trace amounts it leads to high temperature embrittlement (HTE), due intergranular fracture, which results edge cracking during hot rolling. the present work, of a thermodynamic investigation elucidate mechanism are presented. Correlations between HTE, phase formation, and composition Al–Mg alloys were determined. It suggested that: (i) HTE related formation Na-rich liquid phase, significantly weakens strength grain boundaries; (ii) for given Mg content, there exists maximum Na content above cannot be avoided; (iii) alloy, proper hot-rolling should chosen with respect contents suppress HTE. The sensitive zone safe Al–Mg–Na defined as functions processing alloy composition. tendency was evaluated based on thermo...