Friction stir welding（FSW） is used to conduct different welding process contrast experiment of 3 mm thick 6005A alloy plate. Through the mechanical tensile

hardness

forward bending

macro metallographic and micro metallogra-phic analysis of the weld position

the optimal welding process is finally determined. Research shows that when the rotational speed of the friction head is 1 200 r·min

-1

and the welding speed is 700 mm ·min

-1

the mechanical tensile fracture occurs near the heat affected zone and the fracture surface shows "necking" phenomenon

the Vickers hardness distribu-tion is W-shaped

and there are small S-lines in the micro-structure. The mechanical value is higher than the standard and better than the other three welding parameters

which meets the production process requirements and provides technical support for the production process.