Characterization of Phase Formation in Al-20%Mg₂Si-2%Cu Metal Matrix Composite

Abstract:

Advantage of Al-Mg₂Si metal matrix composite (MMC) is due to the particulate reinforced Mg₂Si in the Al matrix that has improved mechanical properties of the in situ composite. In particular, the composite has been chosen as the structural material for automotive and aerospace components. The hypereutectic Al-Mg₂Si composite should be comprised of two morphologies, namely primary Mg₂Si and pseudo-eutectic Al-Mg₂Si phase. However, as-received commercial Al-20Mg₂Si-2Cu in situ composite contained a wide range of elements that affect the resultant microstructure of the in situ composite. In fact, four different morphologies have been identified in the in situ composites. The first phase is dark facet primary Mg₂Si particles, surrounded by pseudo-eutectic Al-Mg₂Si phase in lamellar structure. Along the eutectic boundary is the formation of needle-like Al₅FeSi intermetallic and the phase is surrounded by Al₅Mg₈Si₆Cu₂+Al₂Cu as last phase nucleated. Optical micrograph, SEM imaging, EDX analysis and elemental mapping have revealed these phases correspond to shape of morphologies and respective molecular compound.

• Periodical: Solid State Phenomena (Volume 264)
• Pages: 186-189
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.264.186
• Online since: September 2017
• Authors: Nur Azmah Nordin, Tuty Asma Abu Bakar*, Esah Hamzah, Saeed Farahany, Ali Ourdjini
• Keywords: In Situ Composite, Morphology, Phases

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