▎ 摘　　要

NOVELTY - Improving toughness of aluminum alloy backfilled friction stir spot welding joint comprises selecting block of aluminum alloy plate as target aluminum alloy plate, pre-processing annular groove at center of overlapping area, adding preset quality of graphene, matching size of spot welding tool to size of annular groove, matching volume of annular groove with volume of graphene, placing aluminum alloy plates on target plate of aluminum alloy, and welding two aluminum alloy plates. USE - The method is for improving toughness of aluminum alloy backfilled friction stir spot welding joint. ADVANTAGE - The welding joint has excellent mechanical property.