Comparative hot deformation characters of Al-Mn-Mg-RE alloy and Al-Mn-Mg-RE-Ti alloy

The hot deformation characters of two Al-Mn-Mg-RE alloys (without and with Ti addition, respectively) were studied by hot compression tests, and the deformed microstructures were observed by optical microscopy and transmission electron microscopy, respectively. The results show that the flow stress, hot deformation activation energy and stress exponent were higher with the addition of Ti during hot deformation. Less indistinct subgrain boundaries were also obtained with addition of Ti. The main enriched rare earth constituent particles could make positive purifying effects on impurity elements of Fe and Si in the Al-Mn-Mg-RE alloy. While the addition of Ti not only promoted the formation of a more stable Ti2 Al20 (Cex, La1−x) phase, but also resulted in more refined and dispersive constituent particles, which could improve the hot workability of the alloy.