Effect of MgO Content on Mechanical Properties of Directionally Solidified Pure Magnesium

• Published in: Materials research (São Carlos, São Paulo, Brazil) Vol. 24; no. 2
• Main Authors: Chen, Yuming, Feng, Zhongxue, Zhang, Wanneng
• Format: Journal Article
• Language: English
• Published: ABM, ABC, ABPol 01.01.2021; Associação Brasileira de Metalurgia e Materiais (ABM); Associação Brasileira de Cerâmica (ABC); Associação Brasileira de Polímeros (ABPol)
• Subjects: Diffusion mechanism; Directional solidification; ENGINEERING, CHEMICAL; Magnesium oxide; MATERIALS SCIENCE, MULTIDISCIPLINARY; METALLURGY & METALLURGICAL ENGINEERING; Tensile properties; Directional solidification; Diffusion mechanism; Magnesium oxide; Tensile properties
• ISSN: 1516-1439; 1980-5373; 1980-5373
• DOI: 10.1590/1980-5373-mr-2020-0469

The pure magnesium was fabricated by directional solidification, and the effect of the distribution characteristics of magnesium oxide (MgO) on the mechanical properties of pure magnesium was investigated. The statistical results showed that the area fraction, number and size of MgO were decreased gradually from the top region ingot to the bottom region ingot, and these reflected the advantages of directional solidification technology in the controllability of MgO distribution characteristics. The top parts of magnesium ingots have the highest tensile strength (44 MPa), which is mainly due to the presence of a large amount of the coarse MgO. Though the coarse MgO increases the strength obviously, it has harm for the ductility of magnesium. The top parts of magnesium ingots have higher ultimate tensile strength, but lower failure strain (13% and -21% respectively) than the ingot at the center. These results indicate that if the suitable size and amount of MgO existed in magnesium matrix, it could avoid the disadvantages of MgO and provide positive effect for both the strength and ductility of magnesium alloys.