Static mechanics analyses of different laser weld bonding structures in joining AZ61 Mg alloy

This paper presents the results of recent investigations on laser seam weld bonding (LWB) of magnesium alloy AZ61 sheets. There are two types of LWB structures: perpendicular weld seam (LWB-PE) and parallel weld seam (LWB-PA). In this paper the differences between the two structures are compared and discussed. In tensile shear tests, both LWB-PE and LWB-PA joints can offer higher failure force than that of laser welding or adhesive bonding alone, and LWB-PA joint offers better performance than LWB-PE joint. This is because the weld seam can increase the peel resistance at the free end of the adhesive bonded part, where a stress concentration exists. Maximum T-Peel strengths of LWB joints depend on the laser seam weld. The LWB-PA joint has both the advantages of maximum failure force caused by laser weld and the peel displacement caused by adhesive, so a synergistic effect is obtained in energy absorption.