Tensile behavior of friction-stir-welded AZ31-H24 Mg alloy

In the present study, tensile behavior of friction-stir-welded AZ31 (Mg-3.6Al-1Zn-0.6Mn in wt pct)-H24 Mg alloy was investigated. It was found that the tensile property, particularly tensile elongation, of AZ31-H24 alloy was significantly degraded with friction stir welding (FSW). The tensile fracture always occurred at the boundary between the thermomechanically affected zone (TMAZ) and the stir zone (SZ) on the advancing side. The fractographic examination on the tensile-fractured AZ31-H24 alloy specimen showed a mixed mode of cleavage and dimpled rupture. The AES analysis suggested that the significant reduction in tensile elongation of friction-stir-welded AZ31-H24 Mg alloy was attributable to the entrapped oxides along the boundary between the TMAZ and SZ.