Study On Plastic Deformation Of AZ31 Magnesium Alloy Sheet

Due to its lightweight, high specific strength and electronic shielding, magnesium alloy has been widely used as structural components in the aerospace, electronics, and automobile industry to replace some existing materials. Although the principal manufacturing process has been die casting, the plastic forming has considerable potential because of its competitive productivity and mechanical performance. The plastic forming of wrought magnesium alloy AZ31B was studied systematically in this paper to obtain an optimized manufacturing technique for AZ31B sheet with improved mechanical properties and formability, so that it is possible to develop the"3C"components with high quality.In this paper, The microsegregation, shape and distribution of the second phase formed during solidification were studied with OM,SEM and X-ray deflection. The optimized homogenized technique was found to be at 420℃for 15 hours after analysis of the microstructure evolution and the mechanical properties of as-cast samples heat treated with varied techniques. Compression test of as-cast samples at elevated temperature was conducted on the Gleeble-1500D hot simulator, and the microstructure under different deformation conditions was analyzed. It has been found that the refined microstructure can be obtained when the samples were compressed under 350～450℃at 10s-1. AZ31B sheet was hot rolled following the hot rolling technique which was established on the results of elevated temperature compression test. The microstructure development of hot rolled, cold rolled and heat treated sheet were analyzed and correlated with their tensile mechanical properties.The optimized heat treatment technique was found to be at 250℃for 1 hour. The hot rolled sheet was further cold reduced to 0.84mm thick by direct and cross rolling respectively. Their mechanical properties and r-values were measured in tensile test, and the hardening rate n-values were calculated by linear regression of tensile test data. It has been found after comparative analysis that the cross rolled AZ31B sheet exhibits better formability than the direct rolled one. Stamping test of AZ31B sheet was conduct at elevated temperature in an attempt to pioneer the preliminary task of exploring its forming techniques.