The effect of Ca addition on microstructure and mechanical properties of extruded AZ31 alloys

• Published in: Vacuum 2019-10, Vol.168, p.108822, Article 108822
• Main Authors: Song, Leipeng, Lu, Yalin, Zhang, Yang, Li, Xingcheng, Cong, Mengqi, Xu, Wenting
• Format: Article
• Language: English
• Subjects: AZ31 alloys; Ca addition; Microstructure; Strengthening
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2019.108822

Evolution of microstructure and tensile properties of extruded AZ31 alloys through Ca addition have been systematically investigated in this paper. Results show that Al–Mn and Al2Ca phases scattered along extruding direction exist in extruded AZ31-xCa (0.5 and 1 wt%Ca) alloys. AZ31-1 wt%Ca alloys exhibit finer microstructure with mean grain size of ~2.79 μm in comparison with AZ31-0.5 wt%Ca alloys, which is mainly related to the dynamic recrystallization (DRX) and the inhibition of grain coarsening by Al2Ca phase. In addition, the increased Ca content weakens the {0001} basal texture of extruded AZ31 alloys owing to the formation of Al2Ca phase. The comprehensive mechanical properties of extruded AZ31 alloys have an obvious improvement by adding Ca element owing to the grain refinement strengthening, second phase strengthening and texture strengthening. •The strengthening mechanism of Ca addition on extruded AZ31 was discussed.•The formation of Al2Ca phases induced by adding Ca element could hinder the coarsening of grain of AZ31-xCa alloy.•Adding Ca element to AZ31 alloys led to weakening of texture and improvement of mechanical properties.•Ca element had a better strengthening effect of mechanical properties in comparison with CaO in Mg alloys.