Effects of Nd on microstructure and mechanical properties of Mg–Al–Ca alloy

Abstract

Effects of Nd additions (0–4 wt-) on microstructures and properties of Mg–Al–Ca alloy at room temperature and 150°C have been investigated. The results showed that Mg–6Al–2Ca alloy consisted of α-Mg matrix, Mg₁₇Al₁₂, Mg–Ca and Al–Ca phases. The amount of Al–Nd phase increases with the increasing of Nd content while that of Mg₁₇Al₁₂ decreases. On the other hand, Nd refines the microstructure of as cast and extruded alloys. The ultimate strength and yield strength of experimental alloys are improved with the addition of Nd, and the largest values are 319 and 210 MPa respectively at room temperature. When the temperature was elevated to 150°C, with the increasing of Nd, ultimate strength and yield strength of experimental alloys are first increased and subsequently decreased. Mg–6Al–2Ca–xNd alloy has the best ultimate strength and yield strength at 150°C, which reaches 265 and 179 MPa respectively when the content of Nd reached 3.