Mechanical behaviour of magnesium alloy MMCs produced by squeeze casting and powder metallurgical techniques

Abstract

Magnesium alloy AZ91 was reinforced with alumina short fibres and silicon carbide particles using the powder metallurgical ( P M ) or squeeze casting ( sq c ) techniques. The tensile and fracture toughness tests were carried out at room and elevated temperatures. The effect of reinforcements and fabrication routes on mechanical properties of alloy and composites has been discussed. It was found that the reinforcement increased the tensile related properties and decreased the ductility and fracture toughness of the alloy AZ91. However, a greater influence on mechanical properties has been observed by the fabrication routes. The P M alloy and composites revealed much higher tensile strength and very low fracture toughness compared with the sq c matrix alloy and composite.