PREPARING METHOD OF MANESIUM ALLOY SHEET USING SYMMETRIC AND ASSYMETRIC ROLLING AND THE MAGNESIUM ALLOY SHEET THEREBY

摘要

The purpose of the present invention is to provide a method for manufacturing a magnesium alloy sheet using symmetric and asymmetric rolling and a magnesium alloy sheet manufactured thereby. The method for manufacturing a magnesium alloy sheet using symmetric and asymmetric rolling comprises: a step (step 1) of manufacturing the magnesium alloy sheet; a step (step 2) of asymmetrically rolling the magnesium sheet; a step (step 3) of asymmetrically rolling the magnesium sheet of step 2 after horizontally rotating the magnesium sheet 180 degrees; and a step (step 4) of asymmetrically rolling the magnesium sheet of step 3 after vertically rotating the magnesium sheet 180 degrees. According to the present invention, the method is capable of manufacturing the magnesium alloy sheet with improved mechanical properties such as yield strength, tensile strength, and elongation by rotating the magnesium sheet 180 degrees to change the direction of rolling and performing asymmetric rolling several times when the magnesium alloy sheet is warm-rolled. In particular, a shear band is formed in the magnesium alloy sheet by shearing according to asymmetrical rolling in order to lower the strength of a basic surface, thus increasing elongation rate.