| Magnesium and magnesium alloys are the most light in all of the metal construction materials,its density only contain 1.74/cm~3, is an aluminum of 2/3, lighter than steel 78.1%. Compare with other metals material and engineering plasticses, the magnesium alloy has the very high strength/weight ratio and strength/density ratio. It has excellent dimensional stability and is highly impact and dent resistant. Magnesium has excellent damping capacity and low inertia and recyclable. Such propertiers meet the requirements of kinds of industries(i.e., automobile panels which need to save weight to increase power performance and fuel efficiency, and 3C industris in an attempt to improve the performance and recyclability of their components). The magnesium alloy were already called for 21 centuries'metals, acquiring quickly development in the car, aviation and industry realm in recent years.But for crystal structure of magnesium alloy, its plastic can not compare with aluminum, and the plastic forming ability is bad, as a result magnesium alloy at die-casting forming realm are attached importance and develop. Compared with die-casting magnesium alloys, wrought magnesium alloys with higher strength, ductibility and diversified mechanical properties. For developing the magnesium industry of our country, must strongly develop forming magnesium alloy and its production crafts.This article has conducted the research on the AZ31D magnesium alloy forward extrusion experiment of rectangle section cuboid part and inverted extrusion experiment of one kind of deep micropore part.First, contrasts in an English paper which a doctor of Harbin institute of technology publishes, mentioned thatΦ40mm cylinder AZ31 magnesium alloy had been extruded 35mm×4mm×350mm in the room temperature. The similar experiment had been carried on, and the result proved that under the room temperature it is difficult to obtain the good performance extrusion part. The experimental forming best parameter has been discovered, and the part with good surface quality has been obtained. The forming process has been simulated with the DEFORM-3D software. The load-stroke curve has been obtained and the equivalent stress variation of the simulation process has been analyzed, which is effective to the forward extrusion; The microstructure of extruded part after the forward extrusion have been observed and analyzed. Contrasted to the microstructure of billiet, the microscopic process in the extrusion has been discussed.Then next, one kind of AZ31D magnesium alloy part with deep hole has innovatively carried on backward extrusion experiment, the hole diameter of which only hasΦ3mm and the length/diameter ratio reached as high as 10. The mold has been designed reasonably, and appropriate parameters have been discovered. The deep micropore with good quality has been successfully extruded. The effective FEM simulation has been carried on, which indicated the backward extrusion process is reasonable; The different extrusion depth of micropore has been carried on the microstructure organization observation and the hardness test; the microscopic structural transformation rule in the extrusion process has been analyzed.
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