Dissimilar metal joining method for magnesium alloy and steel

Abstract

[Object] To provide a joining method for dissimilar metals which are magnesium alloy and steel and difficult to be metallurgically directly joined to each other while oxide film is present at a joining surface. [Solving Means] In order to join magnesium alloy material 1 and steel plate 2 to each other, a galvanized steel plate to which Zn—Al—Mg alloy plating (a third material) is applied is used as the steel plate 2. When joining is made, ternary eutectic melting of Al—Mg—Zn is caused, so that it is discharged together with oxide film 1f and impurities from the joining interface while Al—Mg intermetallic compound such as Al3Mg2 and Fe—Al intermetallic compound such as FeAl3 are formed, thereby joining the newly generated surfaces of the magnesium alloy material 1 and the steel plate 2 to each other through a compound layer 3 containing these intermetallic compounds.

Dependencies are inferred from the claim text.