STRAIN-INDUCED AGE STRENGTHENING IN DILUTE MAGNESIUM ALLOY SHEETS

摘要

A method of strengthening a dilute magnesium alloy sheet comprising: (A) providing a dilute magnesium alloy sheet comprising a magnesium alloy consisting essentially of (wt％): >0 to 3.0 of Zn; >0 to 1.5 of Ca; 0 to 1.0 of Zr; 0 to 1.3 of a rare earth element or mixture of the same; 0 to 0.3 of Sr; 0 to 0.7 of Al, the balance of Mg and other unavoidable impurities, wherein the total weight ％ of alloying elements is less than 3％; (B) subjecting the dilute magnesium alloy sheet to plastic deformation, in which the tensile plastic strain should exceed 0.5％, but be less than 8％to form a pre-deformed magnesium alloy sheets; and (C) subjecting the pre-deformed magnesium alloy sheets to an ageing treatment in a temperature range of 80 to 250 ℃ for at least 1 minute, thereby forming a strengthened magnesium alloy sheet.