Powder metallurgy combined with semi-solid extrusion forming were investigated to produce a high strength AZ91D magnesium alloy. In this experiment, machined chips and mechanically ground powder were used for comparisons with castings. Machined chips and milled powder were consolidated by pulse current sintering method in a vacuum state. These three specimens prepared by casting or sintering were extruded through a die measuring 4mm in diameter at the semi-solid temperatures of 723 K and 743 K. This semi-solid state containing a small fraction of liquid phase. The extrusion speed of sintered samples using milled powder is considerably faster than that using castings and consolidated chips. The tensile strength of a rod extruded at 723 K is 350 MPa, and an excellent elongation of 14 % is achieved by the use of consolidated milled powder. This powder metallurgy combined with semi-solid extrusion process successtully realized has produced AZ91D alloy with high strength and near-net-shaping by high-speed extrusion.

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