Processing and Properties of As-Cast Magnesium AM60-Based Composite Containing Alumina Nano Particles and Micron Fibres

Magnesium alloy AM60 based metal matrix composites (MMCs) reinforced with micron alumina (Al2O3) fibres and/or nano-size particles were successfully fabricated by preform-squeeze casting techniques under an applied pressure of 90 MPa. Tensile testing was performed and microstructures were analyzed on as-cast unreinforced AM60 Alloy, fibre reinforced AM60 metal matrix composite, and hybrid AM60 composite containing alumina fibres and nano-particles. The microstructure analysis revealed the homogeneity of reinforcements in the matrix alloy. With the addition of fibres, the tensile properties of the fibre-reinforced composites were improved with the considerable reduction of ductility compared with AM60 alloy. The introduction of additional nano-particles into the metal matrix not only significantly improved the tensile properties of the composites, but also simultaneously restored the ductility reduction caused by the reinforcement of fibres.