مقاله جوشکاری Ultrasonic spot welded AZ31 magnesium alloy: Microstructure, texture, and lap shear strength

مقاله جوشکاری با عنوان : Ultrasonic spot welded AZ31 magnesium alloy: Microstructure, texture, and lap shear strength

V.K. Patel, S.D. Bhole n, D.L. Chen

چکیده:

The structural application of ultra-lightweight magnesium alloys inevitably involves welding and
joining. A solid-state welding – ultrasonic spot welding (USW) – was conducted on AZ31B-H24 Mg
alloy sheet by varying a key parameter of welding energy in this study, aiming to identify the changes
in the microstructure, crystallographic texture, and lap shear tensile strength. The grain size was
observed to increase with increasing welding energy. Crystallographic texture determined via X-ray
diffraction showed a significant change that corresponded well to the change in the deformation and
recrystallization mechanisms of the Mg alloy. The lap shear strength first increased with increasing
energy input, reached the maximum value at a welding energy of 2000 J, then decreased. The welds
generally fractured along the joint interface when the welding energy was lower than 2000 J, while
fracture occurred at the periphery of the joint (button pull-out) for the samples made with an energy
input of higher than 2000 J.