Microstructure and mechanical characterization of cast Mg-Ca-Si alloys

JOURNAL OF ALLOYS AND COMPOUNDS

卷:694

Article

Gil-Santos, Andrea¹  Szakacs, Gabor²  Moelans, Nele¹  Hort, Norbert²  Van der Biest, Omer¹ 

[1] Katholieke Univ Leuven, Dept Mat Engn, Kasteelpk Arenberg 44, B-3001 Leuven, Belgium

[2] Helmholtz Zentrum Geesthacht, Magnesium Innovat Ctr MagIC, Max Planck Str 1, D-21502 Geesthacht, Germany

关键词: Intermetallics;    Rapid-solidification;    Mechanical properties;    Microstructure;   

DOI  :  10.1016/j.jallcom.2016.10.059

来源: Elsevier

【 摘 要 】

Three different phase fields are predicted and experimentally detected in the Mg rich corner of the Mg Ca-Si ternary diagram. The present phases are Mg + MgCaSi + Mg2Si in phase field 1, Mg + MgCaSi in phase field 2 and Mg + Mg2Ca + MgCaSi in phase field 3. The focus of this study is on the formation and evolution of the intermetallic phases. The final microstructures have been related with their solidification process and with the alloys mechanical properties. A clear influence of the observed intermetallic phases on the mechanical performance was found. A bigger size and higher amounts of the MgCaSi intermetallic phase increase the alloys strength and make them brittle, while in its fine morphology MgCaSi reduces the strengthening effect and slightly decreases the ductility compared to pure Mg. Mg2Si phase in its needle-like small size morphology contributes to an increase of the hardness and compressive strength. Its presence reduces the alloys ductility making them brittle. Finally, the highest values for compressive strength and hardness are related to the Mg2Ca presence. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

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