METHOD FOR IMPROVING MOULDABILITY OF MAGNESIUM-ALLOY SHEET MATERIAL, AND MAGNESIUM-ALLOY SHEET MATERIAL PRODUCED THEREBY

摘要

The present invention relates to a method for improving the mouldability of a magnesium-alloy sheet material, and to a magnesium-alloy sheet material produced thereby. The method for improving the mouldability of magnesium-alloy sheet material which is provided comprises the steps of: forming {10-12} bicrystals in the magnesium-alloy sheet material (step 1); and subjecting the magnesium-alloy sheet material of step 1 to an annealing heat treatment (step 2). Also, the magnesium-alloy sheet material which is provided comprises {10-12} bicrystals produced by means of the method. The method for improving the mouldability of a magnesium-alloy sheet material according to the present invention has the advantages that it is possible to artificially form {10-12} bicrystals in the magnesium alloy without any increase in electrical potential since compression deformation is applied to the magnesium-alloy sheet material in a direction parallel to the basal plane of the structure possessed by the sheet material, and also that it is possible to improve the mouldability of magnesium-alloy sheet materials at room temperature and when hot since the bicrystals easily absorb deformation that occurs during moulding through annihilation.