| Magnesium metal was recognized in 1808. Germany did't used it in industry field until 1886. Magnesium has been used for a wide variety of application, including pyrotechnics and metallurgical, chemical, electrochemical, and structural applications. Due to its many attractive properties, including low specific gravity, high specific strength, excellent damping capacity etc., magnesium alloys have been successfully used in various structures such as navigation, space flight, 3C product, power tool and traffic etc. These structures are almost castings, in the main, are pressure die castings used in the automobiles. High property wrought magnesium alloy is in a period of study and popularizing. Compared with steel and aluminum alloy, magnesium alloy has some limitation such as lower strength and worse ductility etc. It is key to accelerate development of magnesium alloy industry how the strength of magnesium alloy is improved. This paper is devoted to improving the strength of AZ series magnesium alloy to apply in a certain type of producing shell by ductility distortion and heat treatment.In order to perform that magnesium alloys were used in cap, fuse and flame hull of a certain type of shell, This paper has done many study works, including analyzing the newest study and application of wrought magnesium alloy, the three parts'application environment, choosing magnesium alloy material and process, studying AZ61 and AZ80 carefully to improve the properties of magnesium alloys, manufacturing the parts and assembling them and testing the final performance.The study method of this paper is that the ingots are extruded through a die to form rod , the properties of rod are tested , the microstructure of it are analyzed by optical microscopy , scan electron miroscopy(SEM) and X-ray diffraction(XRD) after heat treatment, consequently the relations of process and mechanics properties were found out. The high strength AZ61 and AZ80 wrought magnesium alloy which satisfied with the shell's properties and heat treatment process are obtained. The evolution rule of structure and properties was analyzed by the theory of metallography and heat treatment.By investigation, the heat treatment process of AZ61 used in cap is that the extruded alloy is aged in 180°C with 24 hours after it is dissolved in 350°C with 2 hours, that of AZ80 used in fuse and flame hull is that the alloy is aged in 170°C with 20 hours after it is dissolved in 400°C with 3 hours. The magnesium alloy produced by this process has been manufactured into the shell parts. It is proved that the main items of the alloy satisfied completely all requirement of the product.
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