2009 年 27 巻 2 号 p. 183s-186s
The effects of zinc insert and Al content in Mg alloy on the bondability in steel/Mg alloy joints were evaluated using SEM, EDX, XRD and tensile test. A cold rolled steel plate (SPCC), a zinc coated steel (GI), Mg-3mass% Al alloy (AZ31) and Mg-6mass% Al alloy (AZ61) were used in this study. The bondability of the joints using zinc insert were significantly improved, because Zn-Mg eutectic reaction efficiently removes the oxide films on the Mg alloy. While a thin Fe-Al type interfacial reaction layer was formed discontinuously in GI/AZ31 joint, a Fe-Al and Al-Mg combined interfacial reaction layer was continuously formed in GI/AZ61 joint. These microstructural changes leads to mechanical properties of the joints, that is, the joint strength was improved from 40MPa in GI/AZ31 joint to 70MPa in GI/AZ61 joint.
