Magnesium Matrix Composite with Solid-state Synthesized Mg₂Si Dispersoids

Abstract

For improvement of the mechanical properties of magnesium alloys, the material and process design for MMC was established to disperse solid-state synthesized Mg₂Si in the magnesium alloys, in employing the elemental magnesium and silicon powder mixture. In the repeated plastic working on the raw mixture for the refinement of silicon particles and their uniform distribution in the AZ31 primary powder, Mg₂Si/Mg composite alloys show fine microstructures and superior mechanical properties: UTS is about 350 MPa and YS is over 300 MPa. This is because of fine Mg₂Si dispersoids with a mean particle size less than 5 μm as well as refined matrix grain of 2–5 μm. The specific tensile strength is much higher than that of the conventional magnesium and aluminum alloys such as AZ31, AZ91 and 2014(T6) alloys. This material and process design is possible to apply to the mass-production process in using a large scale manufacturing equipments.