The invention discloses an aluminum
alloy workpiece additive manufacturing method implemented through
friction stir welding. On the basis of an existing
electric arc additive manufacturing aluminum
alloy workpiece, the characteristic that aluminum
alloy is soft in property is combined, after an aluminum alloy workpiece is manufactured from
electric arc additives layer by layer,
friction stir welding intensification treatment is conducted on each layer, and therefore, defects such as pass gaps, interlayer incomplete fusion, air holes and the like can be eliminated through friction stir weldingwhen each layer is manufactured. Compared with the pure
electric arc additive manufacturing aluminum alloy workpiece, by means of the method, the structural state of the aluminum alloy workpiece obtained through additive manufacturing can be improved; the grains can be finer; second-phase grains are finer and are distributed more uniformly; and the
dislocation density achieved in the aluminum alloy additive manufacturing workpiece is increased. Compared with existing
friction stir welding intensification, grain refining and defect
elimination are conducted on each layer of the workpiece so that the strength of the whole workpiece can be improved rather than only
surface modification, namely surface intensification, is conducted.