TY - JOUR

T1 - Microstructure and mechanical characterization of cast Mg-Ca-Si alloys

AU - Gil-Santos, Andrea

AU - Szakacs, Gabor

AU - Moelans, Nele

AU - Hort, Norbert

AU - Van der Biest, Omer

PY - 2017/2/15

Y1 - 2017/2/15

N2 - 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.

AB - 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.

KW - Intermetallics

KW - Mechanical properties

KW - Microstructure

KW - Rapid-solidification

KW - Engineering

UR - http://www.scopus.com/inward/record.url?scp=84991720052&partnerID=8YFLogxK

U2 - 10.1016/j.jallcom.2016.10.059

DO - 10.1016/j.jallcom.2016.10.059

M3 - Journal articles

AN - SCOPUS:84991720052

VL - 694

SP - 767

EP - 776

JO - Journal of Alloys and Compounds

JF - Journal of Alloys and Compounds

SN - 0925-8388

ER -