Effects of Substitution of Y with Yb and Ce on the Microstructures and Mechanical Properties of Mg_88.5Zn₅Y_6.5

• Main Authors: Hongxin Liao, Taekyung Lee, Jiangfeng Song, Jonghyun Kim, Fusheng Pan
• Format: Article
• Language: English
• Published: MDPI AG 2021-12-01
• Series: Metals
• Subjects: Mg-Zn-Y-RE; long-period stacking ordered structure; mechanical properties; creep resistance
• Online Access: https://www.mdpi.com/2075-4701/11/1/31

The microstructures and mechanical properties of the Mg₈₈_.₅Zn₅Y₆_._5-XRE_X (RE = Yb and Ce, X = 0, 1.5, 3.0, and 4.5) (wt.%) alloys were investigated in the present study. Mg_88.5Zn₅Y_6.5 is composed of three phases, namely, α-Mg, long-period stacking ordered (LPSO) phases, and intermetallic compounds. The content of the LPSO phases decreased with the addition of Ce and Yb, and no LPSO phases were detected in Mg_88.5Zn₅Y_2.0Yb_4.5. The alloys containing the LPSO phases possessed a stratified microstructure and exhibited excellent mechanical properties. Mg_88.5Zn₅Y_5.0Ce_1.5 exhibited the highest creep resistance and mechanical strength at both room temperature and 200 °C, owing to its suitable microstructure and high thermal stability. The yield strength of Mg_88.5Zn₅Y_5.0Ce_1.5 at room temperature was 358 MPa. The ultimate tensile strength of Mg_88.5Zn₅Y_5.0Ce_1.5 at room temperature and 200 °C was 453 MPa and 360 MPa, respectively.