| Our country has large abundant of resource of magnesium which has been widely used. Because of its poor plasticity, low ignition point and oxidizability, the deformation of magnesium became a new problem. Rheo-extrusion forming process realized the continuous production from high temperature liquid to sectional material of magnesium alloy. The property was better than the material casting state and the cost is reduced. So rheo-extrusion forming process had epoch-making purpose for the development and application of the magnesium alloy.This paper is based on the theory of rheo-extrusion forming process and elected the AZ31 magnesium alloy as object. The technology of rheo-extrusion forming process and metal flow were studied in this paper. Then the products were treated by solid solution and aging process. Through the OM,SEM and mechanical property test, some achievement obtained:(1) The products of AZ31 magnesium alloy were produced though the Castex process. Eventually, the optimum technology scheme was determined. The casting temperature was 750℃and the capacity of cooling water was between 35L/min and 45L/min.(2) Theβphase which distributed as reticulate structure between fir-tree crystal fused into the magnesium alloy base though solid solution treat. Theβ-phase fused intoα-base sufficiently when solid solution temperature rose and time elongated.(3) The perceptible mechanism whichβphase precipitate from base among aging process had two kinds:continuous precipitation and discontinuous precipitation. The hardness of products decreased as the long of solid solution time whenβphase fuse into base. The hardness decreased a little as long of aging time when P phase precipitate to a certain degree.(4) Though solid solution and aging process, tensile strength arrived at 250Mp, yield strength arrived at 120MP, extensibility arrived at 25% and improved plasticity.
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